<s> [INST] <<SYS>> You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information. <</SYS>> What is Amantadine and explain in detail? [/INST] Amantadine, sold under the brand name Gocovri among others, is a medication used to treat dyskinesia associated with parkinsonism and influenza caused by type A influenzavirus, though its use for the latter is no longer recommended due to widespread drug resistance. It acts as a nicotinic antagonist, dopamine agonist, and noncompetitive NMDA antagonist. The antiviral mechanism of action is antagonism of the influenzavirus A M2 proton channel, which prevents endosomal escape (i.e. the release of viral genetic material into the host cytoplasm).Amantadine was first used for the treatment of influenza A. After antiviral properties were initially reported in 1963, amantadine received approval for prophylaxis against the influenza virus A in 1976. However, amantadine-resistant influenza viruses were first reported during the 1980 influenza A epidemic and resistance frequency continued to rise into the early 2000s. Currently, amantadine is no longer recommended for the treatment of influenza A due to a high level of amantadine resistance among circulating influenza A viruses. In 1973, the Food and Drug Administration (FDA) approved amantadine for use in the treatment of Parkinsons disease. In 2017, the extended release formulation was approved for use in the treatment of levodopa-induced dyskinesia. Off-label uses include improvement of fatigue in multiple sclerosis and accelerating the rate of functional recovery and arousal following a brain injury.Amantadine has a mild side effect profile. Common neurological side effects include drowsiness, light headedness, dizziness, and confusion. Due to its effects on the central nervous system, it should not be combined with additional CNS stimulants or anticholinergic drugs. Amantadine is contraindicated in persons with end stage kidney disease, given that the drug is cleared by the kidneys. It should also be taken with caution in those with enlarged prostates or glaucoma, due to its anticholinergic effects. Live attenuated vaccines are contraindicated while taking amantadine, as it may limit the efficacy of the administered vaccine.

Chemical structure
Amantadine (brand names Gocovri, Symadine, and Symmetrel) is the organic compound 1-adamantylamine or 1-aminoadamantane, which consists of an adamantane backbone with an amino group substituted at one of the four methyne positions. Rimantadine is a closely related adamantane derivative with similar biological properties; both target the M2 proton channel of influenza A virus.

Mechanism of action
Parkinsons disease
The mechanism of its antiparkinsonian effect is poorly understood. Amantadine is a weak antagonist of the NMDA-type glutamate receptor, increases dopamine release, and blocks dopamine reuptake. Amantadine probably does not inhibit monoamine oxidase (MAO) enzyme. Moreover, the drug has many effects in the brain, including release of dopamine and norepinephrine from nerve endings. It appears to be an anticholinergic (specifically at alpha-7 nicotinic receptors) like the similar pharmaceutical memantine.In 2004, it was discovered that amantadine and memantine bind to and act as agonists of the σ1 receptor (Ki = 7.44 μM and 2.60 μM, respectively), and that activation of the σ1 receptor is involved in the dopaminergic effects of amantadine at therapeutically relevant concentrations. These findings may also extend to the other adamantanes such as adapromine, rimantadine, and bromantane, and could explain the psychostimulant-like effects of this family of compounds.

Influenza
The mechanisms for amantadines antiviral and antiparkinsonian effects are unrelated. Amantadine targets the influenza A M2 ion channel protein. The M2 proteins function is to allow the intracellular virus to replicate (M2 also functions as a proton channel for hydrogen ions to cross into the vesicle), and exocytose newly formed viral proteins to the extracellular space (viral shedding). By blocking the M2 channel, the virus is unable to replicate because of impaired replication, protein synthesis, and exocytosis.Amantadine and rimantadine function in a mechanistically identical fashion, entering the barrel of the tetrameric M2 channel and blocking pore function—i.e., proton translocation.Resistance to the drug class is a consequence of mutations to the pore-lining amino acid residues of the channel, preventing both amantadine and rimantadine from binding and inhibiting the channel in their usual way.

Pharmacokinetics
Amantadine is well absorbed orally. The onset of action is usually within 48 hours when used for parkinsonian syndromes, including dyskinesia. As plasma concentrations of amantadine increase, there is a greater risk for toxicity.Half-life elimination averages eight days in patients with end-stage kidney disease. Amantadine is only minimally removed by hemodialysis.Amantadine is metabolized to a small extent (5-15%) by acetylation. It is mainly excreted (90%) unchanged in urine by kidney excretion.

Medical uses
Parkinsons disease
Amantadine is used to treat Parkinsons disease-related dyskinesia and drug-induced parkinsonism syndromes. Amantadine may be used alone or in combination with another anti-Parkinsons or anticholinergic drug. The specific symptoms targeted by amantadine therapy are dyskinesia and rigidity. The extended release amantadine formulation is commonly used to treat dyskinesias in people receiving levodopa therapy for Parkinsons disease. A 2003 Cochrane review had concluded there was insufficient evidence to prove the safety or efficacy of amantadine to treat dyskinesia.In 2008, the World Health Organization reported amantadine is not effective as a stand-alone parkinsonian therapy, but recommended it could be used in combination therapy with levodopa.

Influenza A
Amantadine is not recommended for treatment or prophylaxis of influenza A in the United States. Amantadine has no effect preventing or treating influenza B infections. The US Centers for Disease Control and Prevention found 100% of seasonal H3N2 and 2009 pandemic flu samples were resistant to adamantanes (amantadine and rimantadine) during the 2008–2009 flu season.The U.S. Centers for Disease Control and Prevention (CDC) guidelines recommend only neuraminidase inhibitors for influenza treatment and prophylaxis. The CDC recommends against amantadine and rimantadine to treat influenza A infections.Similarly, the 2011 World Health Organization (WHO) virology report showed all tested H1N1 influenza A viruses were resistant to amantadine. WHO guidelines recommend against use of M2 inhibitors for influenza A. The continued high rate of resistance observed in laboratory testing of influenza A has reduced the priority of M2 resistance testing.A 2014 Cochrane review did not find evidence for efficacy or safety of amantadine used for the prevention or treatment of influenza A.

Extra-pyramidal side effects
An extended release formulation is used to treat levodopa-induced dyskinesia in patients with Parkinsons disease. The WHO recommends the use of amantadine as a combination therapy to reduce levodopa side effects.

Off-label uses
Fatigue in multiple sclerosis
Amantadine, along with modafinil and methylphenidate, are the most commonly used medications for the treatment of multiple sclerosis (MS) related fatigue in clinical practice. A 2007 Cochrane literature review concluded that there was no overall evidence supporting the use of amantadine in treating fatigue in patients with MS. A follow up 2012 Cochrane review stated that there may be some amantadine-induced improvement in fatigue in some people with MS. Despite multiple control trials that have also demonstrated improvements in subjective and objective ratings of fatigue, there is no final conclusion regarding its effectiveness.Consensus guidelines from the German Multiple Sclerosis Society (GMSS) in 2006 state that amantadine produces moderate improvement in subjective fatigue, problem solving, memory, and concentration. Thus, GMSS guidelines strongly recommend the use of amantadine in MS-related fatigue.In the UK NICE recommends considering amantadine for MS fatigue.

Awareness in patients with disorders of consciousness
Disorders of consciousness (DoC) include coma, vegetative state (VS), and minimally conscious state (MCS). Amantadine has been shown to increase the rate of emergence from a MCS, defined by consistent demonstration of interactive communication and functional objective use. In traumatic brain injury patients in the intensive care unit, amantadine has also been shown in various randomized control trials to increase the rate of functional recovery and arousal, particularly in the time period immediately following an injury. There are also reports of significantly improved consciousness in patients treated for non-traumatic cases of DoC, such as in the case of a subarachnoid hemorrhage, cerebral hemorrhage, and hypoxic encephalopathy. In 2018 the American Academy of Neurology (AAN) updated treatment guidelines on the use of amantadine for patients with prolonged DoC, recommending the use of amantadine (100–200 mg bid) for adults with DoC 4–16 weeks post injury to support early functional recovery and reduce disability.

Neuroplasticity and overall functional recovery in patients with brain injury
In various studies, amantadine and memantine have been shown to accelerate the rate of recovery from a brain injury. The time-limited window following a brain injury is characterized by neuroplasticity, or the capacity of neurons in the brain to adapt and compensate after injury. Thus, physiatrists will often start patients on amantadine as soon as impairments are recognized. There are also case reports showing improved functional recovery with amantadine treatment occurring years after the initial brain injury. There is insufficient evidence to determine if the functional gains are a result of effects through the dopamine or norepinephrine pathways. Some patients may benefit from direct dopamine stimulation with amantadine, while others may benefit more from other stimulants that act more on the norepinephrine pathway, such as methylphenidate. It is unclear if treatment with amantadine improves long-term outcomes or simply accelerates recovery. Nonetheless, amantadine-induced acceleration of recovery reduces the burden of disability, lessens health care costs, and minimizes psychosocial stressors in patients.

Adverse effects
Amantadine is generally well tolerated and has a mild side-effect profile.

Neurological
Side effects include drowsiness (especially while driving), lightheadedness, falls, and dizziness. Patients on amantadine should avoid combination with other central nervous system (CNS) depressing agents, such as alcohol. Excessive alcohol usage may increase the potential for CNS effects such as dizziness, confusion, and light headedness.Rare severe adverse effects include neuroleptic malignant syndrome, depression, convulsions, psychosis, and suicidal ideation. It has also been associated with disinhibited actions (gambling, sexual activity, spending, other addictions) and diminished control over compulsions.

Cardiovascular
Amantadine may cause orthostatic hypotension, syncope, and peripheral edema.

Gastrointestinal
Amantadine has also been associated with dry mouth and constipation.

Skin
Rare cases of skin rashes, such as Stevens–Johnson syndrome and livedo reticularis have also been reported in patients treated with amantadine.

Pregnancy and lactation
Amantadine is Food and Drug Administration category C for pregnancy. Teratogenic effects have been observed in humans (case reports) and animal reproduction studies. Amantadine may also be present in breast milk and negatively alter breast milk production or excretion. The decision to breastfeed during amantadine therapy should consider the risk of infant exposure, the benefits of breastfeeding, and the benefits of the drug to the mother.

Interactions
Amantadine may affect the central nervous system due to dopaminergic and anticholinergic properties. The mechanisms of action are not fully known. Because of the CNS effects, caution is required when prescribing additional CNS stimulants or anticholinergic drugs. Thus, concurrent use of alcohol with Amantadine is not recommended due to enhanced CNS depressant effects. In addition, anti-dopaminergic drugs such as metoclopramide and typical anti-psychotics should be avoided. These interactions are likely related to opposing dopaminergic mechanisms of action, which inhibits amantadines anti-Parkinson effects.

Contraindications
Amantadine is contraindicated in persons with end stage kidney disease. The drug is renally cleared.Amantadine may have anticholinergic side effects. Thus, patients with an enlarged prostate or glaucoma should use with caution.Live attenuated vaccines are contraindicated while taking amantadine. It is possible that amantadine will inhibit viral replication and reduce the efficacy of administered vaccines. The U.S. Food and Drug Administration recommends avoiding amantadine for two weeks prior to vaccine administration and 48 hours afterward.

History
Influenza A
Antiviral properties were first reported in 1963 at the University of Illinois Hospital in Chicago. In this amantadine trial study volunteer college students were exposed to a viral challenge. The group that received amantadine (100 milligrams 18 hours before viral challenge) had less Asia influenza infections than the placebo group. Amantadine received approval for the treatment of influenza virus A in adults in 1976. It was first used in West Germany in 1966. Amantadine was approved by the U.S. Food and Drug Administration in October 1968, as a prophylactic agent against Asian (H2N2) influenza and received approval for prophylactic use for influenza A in 1976.During the 1980 influenza A epidemic, the first amantadine-resistance influenza viruses were reported. The frequency of amantadine resistance among influenza A (H3N2) viruses from 1991 and 1995 was as low as 0.8%. In 2004 the resistance frequency increased to 12.3%. A year later resistance increase significantly to 96%, 72%, and 14.5% in China, South Korea, and the United States, respectively. By 2006, 90.6% of H3N2 strains and 15.6% of H1N1 were amantadine-resistant. A majority of the amantadine-resistant H3N2 isolates (98.2%) were found to contain an S31N mutation in the M2 transmembrane domain that confers resistance to amantadine. Currently, adamantane resistance is high among circulating influenza A viruses. Thus, they are no longer recommended for treatment of influenza A.

Parkinsons disease
An incidental finding in 1969 prompted investigations about amantadines effectiveness for treating symptoms of Parkinsons disease. A woman with Parkinsons disease was prescribed amantadine to treat her influenza infection and reported her cogwheel rigidity and tremors improved. She also reported that her symptoms worsened after she finished the course of amantadine. The published case report was not initially corroborated by any other instances by the medical literature or manufacturer data. A team of researchers looked at a group of ten patients with Parkinsons disease and gave them amantadine. Seven of the ten patients showed improvement, which was convincing evidence for the need of a clinical trial, which included 163 patients with Parkinsons disease and 66% experienced subjective or objective reduction of symptoms with a maximum daily dose of 200 mg. Additional studies followed patients for greater lengths of time and in different combinations of neurological drugs. It was found to be a safe drug that could be used over long periods of time with few side effects as monotherapy or in combination with L-dopa or anti-cholinergic drugs. By April 1973, the U.S. Food and Drug Administration approved amantadine for use in the treatment of Parkinsons disease.In 2017, the U.S. Food and Drug Administration approved the use of amantadine in an extended release formulation for the treatment of dyskinesia, an adverse effect of levodopa in people with Parkinsons disease.

Veterinary misuse
In 2005, Chinese poultry farmers were reported to have used amantadine to protect birds against avian influenza. In Western countries and according to international livestock regulations, amantadine is approved only for use in humans. Chickens in China have received an estimated 2.6 billion doses of amantadine </s>


<s> [INST] <<SYS>> You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information. <</SYS>> What is Eteplirsen and explain in detail? [/INST] Eteplirsen (brand name Exondys 51) is a medication to treat, but not cure, some types of Duchenne muscular dystrophy (DMD), caused by a specific mutation. Eteplirsen only targets specific mutations and can be used to treat about 14% of DMD cases. Eteplirsen is a form of antisense therapy.
Eteplirsen was developed by Steve Wilton, Sue Fletcher and colleagues at the University of Western Australia and commercialized by Sarepta Therapeutics. After a controversial debate surrounding the drugs efficacy, during which two FDA review panel members resigned in protest, eteplirsen received accelerated approval from the US Food and Drug administration in late 2016. The Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency (EMA) refused to authorize the use of eteplirsen.

Adverse effects
The following adverse events were observed in at least 10% of people who received eteplirsen in trials: vomiting, contusion, excoriation, arthralgia, rash, catheter site pain, and upper respiratory tract infection.

Mechanism of action
Duchenne muscular dystrophy is caused when a mutation in the DMD gene changes the DMD mRNA so that it no longer codes for functional dystrophin protein, usually due to a nonsense mutation that introduces a premature stop codon into the mRNA. If an exon with an appropriate number of bases lies near the mutation, by removing the defective exon the downstream reading frame can be corrected and production of partially functional dystrophin can be restored.  This is the general strategy used for designing exon-skipping oligos for DMD; as there are 79 exons transcribed in the longest splice form of the dystrophin transcript, many different oligos are needed to address the range of mutations present in the population of people with DMD.Eteplirsen is a morpholino antisense oligomer which triggers excision of exon 51 during pre-mRNA splicing of the dystrophin RNA transcript.  Skipping exon 51 changes the downstream reading frame of dystrophin; giving eteplirsen to a healthy person would result in production of dystrophin mRNA which would not code for functional dystrophin protein but, for DMD patients with particular nonsense mutations, giving eteplirsen can restore the reading frame of the dystrophin mRNA and result in production of functional (although modified by having an internal deletion consisting of both the patients original defect, as well as the therapeutically skipped exon) dystrophin.  Eteplirsen is given by intravenous infusion for systemic treatment of DMD.
Exon skipping is induced by eteplirsen, a charge-neutral, phosphorodiamidate morpholino oligomer (PMO) that selectively binds to exon 51 of dystrophin pre-mRNA, restoring the phase of the reading frame and enabling production of functional, but internally edited, dystrophin. The uncharged nature of the PMO helps make it resistant to biological degradation. This modified dystrophin protein produced by eteplirsen may cause a less severe form of dystrophinopathy, much like Becker muscular dystrophy. Eteplirsens proposed mechanism of action is to bind to dystrophin pre-mRNA and alter the exon splicing of the RNA so that more almost full-length dystrophin is made. By increasing the quantity of an abnormal, but potentially functional, dystrophin protein, the objective is to slow or prevent the progression of DMD.

Nature and sequence of oligo and target
Eteplirsen is a morpholino phosphorodiamidate antisense oligomer.
CTCCAACATCAAGGAAGATGGCATTTCTAG (sequence source: US FDA ETEPLIRSEN BRIEFING DOCUMENT NDA 206488),
30-mer,
20% G,
43% CG,
Predicted Tm: 88.9 °C at 10 μM oligo.
Oligo complement
CTAGAAATGCCATCTTCCTTGATGTTGGAG
DMD-001 Exon 51, ENST00000357033.8 in Ensembl.org, RNA target site marked. Given that the target site is within an exon, this is likely blocking binding of an exonic splice enhancer protein and so altering splicing by interfering with splice regulation.
CTCCTACTCAGACTGTTACTCTGGTGACACAACCTGTGGTTACTAAGGAAACTGCCATCT
CCAAA[CTAGAAATGCCATCTTCCTTGATGTTGGAG]GTACCTGCTCTGGCAGATTTCAACC
GGGCTTGGACAGAACTTACCGACTGGCTTTCTCTGCTTGATCAAGTTATAAAATCACAGA
GGGTGATGGTGGGTGACCTTGAGGATATCAACGAGATGATCATCAAGCAGAAG

Pharmacokinetics
Following single or multiple intravenous infusions, the majority of drug elimination occurred within 24 hours of intravenous administration. Elimination half-life of eteplirsen was 3 to 4 hours.

History
New Drug Applications (NDA) for eteplirsen and a similar drug drisapersen were filed with the US Food and Drug Administration (FDA) in August 2015. The Prescription Drug User Fee Act (PDUFA) goal dates for these were December 27, 2015 for drisapersen and February 26, 2016, for eteplirsen. Following FDA rejection of drisapersen, the agency announced a three-month time extension for its review of eteplirsen. The FDA panel decision was controversial because the FDA staff and the panel used a stricter standard of evidence than Sarepta and patient groups used. The FDA panel said that it was required by law to apply the standard of "substantial evidence" of effectiveness </s>


<s> [INST] <<SYS>> You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information. <</SYS>> What is Norgestimate and explain in detail? [/INST] Norgestimate, sold under the brand names Ortho Tri-Cyclen and Previfem among others, is a progestin medication which is used in birth control pills for women and in menopausal hormone therapy. The medication is available in combination with an estrogen and is not available alone. It is taken by mouth.Side effects of the combination of an estrogen and norgestimate include menstrual irregularities, headaches, nausea, abdominal pain, breast tenderness, mood changes, and others. Norgestimate is a progestin, or a synthetic progestogen, and hence is an agonist of the progesterone receptor, the biological target of progestogens like progesterone. It has very weak androgenic activity and no other important hormonal activity. The medication is a prodrug of norelgestromin and to a lesser extent of levonorgestrel in the body.Norgestimate was patented in 1965 and introduced for medical use, specifically in birth control pills, in 1986. It was introduced for use in menopausal hormone therapy in the United States in 1999. Norgestimate is sometimes referred to as a "third-generation" progestin. It is marketed in birth control pills widely throughout the world, whereas it is available for use in menopausal hormone therapy only in the United States and Brazil. Norgestimate is available as a generic medication. In 2019, the version with ethinylestradiol was the 70th most commonly prescribed medication in the United States, with more than 10 million prescriptions.

Medical uses
Norgestimate is used in hormonal contraception and in menopausal hormone therapy for the treatment of menopausal symptoms. It is used in combination with ethinylestradiol in birth control pills and in combination with estradiol in menopausal hormone therapy.

Available forms
Norgestimate is available only in combination with the estrogens ethinylestradiol and estradiol. These formulations are for use by mouth and are indicated specifically for hormonal contraception and menopausal hormone therapy. Norgestimate is not available on its own (i.e., as a standalone medication).

Contraindications
Side effects
Norgestimate has mostly been studied in combination with an estrogen, so the side effects of norgestimate specifically or on its own have not been well-defined.Side effects associated with the combination of ethinylestradiol and norgestimate in premenopausal women, with greater than or equal to 2% incidence over up to 24 menstrual cycles, include headache/migraine (33%), abdominal/gastrointestinal pain (7.8%), vaginal infection (8.4%), vaginal discharge (6.8%), breast issues (including breast pain, discharge, and enlargement) (6.3%), mood disorders (including depression and mood alterations) (5.0%), flatulence (3.2%), nervousness (2.9%), and rash (2.6%).Side effects associated with the combination of estradiol and norgestimate in postmenopausal women, with greater than or equal to 5% incidence over one year, include headache (23%), upper respiratory tract infection (21%), breast pain (16%), back pain (12%), abdominal pain (12%), flu-like symptoms (11%), arthralgia (9%), vaginal bleeding (9%), dysmenorrhea (8%), sinusitis (8%), vaginitis (7%), pharyngitis (7%), fatigue (6%), pain (6%), nausea (6%), viral infection (6%), flatulence (5%), tooth disorder (5%), myalgia (5%), dizziness (5%), depression (5%), and coughing (5%).

Overdose
Interactions
Pharmacology
Pharmacodynamics
Norgestimate is a rapidly and completely converted prodrug, mainly of norelgestromin (17β-deacetylnorgestimate or levonorgestrel 3-oxime), but also of levonorgestrel (3-keto-17β-deacetylnorgestimate) to a lesser extent (22 ± 6% of an administered dose or about 40–70 µg) and of levonorgestrel acetate (levonorgestrel 17β-acetate) in very small amounts. Via its active metabolites, norgestimate has progestogenic activity, antigonadotropic effects, very weak androgenic activity, and no other important hormonal activity.

Progestogenic activity
Norgestimate is a progestogen, or an agonist of the progesterone receptor. The relative binding affinities of norgestimate and its active metabolites for the progesterone receptor compared to promegestone (100%) are 15% for norgestimate, 10% for norelgestromin, 150% for levonorgestrel, and 135% for levonorgestrel acetate. Because of their low concentrations, norgestimate and levonorgestrel acetate are not thought to contribute significantly to the biological activity of norgestimate. In addition, although levonorgestrel binds to the progesterone receptor with much higher affinity than norelgestromin, levonorgestrel has high affinity for sex hormone-binding globulin (SHBG) (87% of that of testosterone), which may limit its activity, whereas norelgestromin does not bind to SHBG. The ovulation-inhibiting dosage of norgestimate is 200 µg/day.

Androgenic activity
In addition to its progestogenic activity, norgestimate has weak androgenic activity. However, the medication shows less androgenic activity than related 19-nortestosterone progestins like levonorgestrel and norethisterone. Norgestimate and norelgestromin have negligible affinity for the androgen receptor (both 0% of the affinity of metribolone), while levonorgestrel has considerable affinity for the androgen receptor (45% of that of metribolone). In addition to their lack of affinity for the androgen receptor, norgestimate and norelgestromin have virtually no affinity for SHBG, and therefore do not displace testosterone from this carrier protein (although levonorgestrel does still bind with high affinity to SHBG and hence could increase free testosterone levels via occupation of SHBG). In accordance, clinical trials of norgestimate have observed minimal androgenic side effects in women treated with the medication. As an example, clinical studies have found that norgestimate does not appreciably inhibit the increase in SHBG levels produced by ethinylestradiol. This is of interest because estrogens increase and androgens decrease liver production of SHBG and by extension circulating levels of SHBG.The relative binding affinity of norgestimate and its metabolite norelgestromin for the rat prostatic androgen receptor (AR) are 0.3% and 1.3% of those of dihydrotestosterone (DHT), respectively, whereas the respective values for levonorgestrel and gestodene are 22% and 15%. Based on these findings, the ratios of AR to PR binding are 219 for norgestimate and 48 for norelgestromin, whereas the ratios for progesterone, levonorgestrel, and gestodene are 93, 11, and 28, respectively. As such, norgestimate and norelgestromin would appear to have much lower androgenic potency than other 19-nortestosterone progestins. However, levonorgestrel is an important metabolite of both norgestimate and norelgestromin, and it may serve to increase their androgenic potency to some degree.When norgestimate is combined with ethinylestradiol, which is potently antiandrogenic, there are only antiandrogenic effects overall and the combination is suitable for treatment of hyperandrogenism.

Other activities
Norgestimate and its active metabolites do not bind to other steroid hormone receptors besides the progesterone and androgen receptors and hence have no other off-target hormonal activity. This includes estrogenic, glucocorticoid, antimineralocorticoid, and neurosteroid activity. However, levonorgestrel has been found to inhibit 5α-reductase and hepatic cytochrome P450 enzymes in vitro to some extent.

Pharmacokinetics
Norgestimate is rapidly and almost completely metabolized into its active metabolites, mainly norelgestromin (the primary active metabolite) and to a lesser extent levonorgestrel, upon oral ingestion. As a result, only very low concentrations (70 pg/mL) of norgestimate itself are detectable in the circulation, and only for about 6 hours after an oral dose. The oral bioavailability of norgestimate is unknown. This is due to the rapid and extensive metabolism of norgestimate, which makes determination of overall bioavailability difficult and necessitates methods other than area-under-the-curve (AUC) to do so. Peak levels of norelgestromin (3,500 pg/mL) are reached at approximately 2 hours following administration of norgestimate. Co-administration of norgestimate with a high-fat meal has been found to significantly decrease peak levels of norelgestromin, although the area-under-the-curve levels of norelgestromin are not significantly altered by food. Steady-state levels of norelgestromin and levonorgestrel are reached within 21 days of treatment with norgestimate. There is an approximate 2-fold accumulation in levels of norelgestromin and a non-linear approximate 8-fold accumulation in levels of levonorgestrel with continuous administration of norgestimate. The accumulation of levonorgestrel is thought to be a result of its high affinity for SHBG, which limits its biological activity. The plasma protein binding of norelgestromin is approximately 99% and it is bound to albumin but not to SHBG. Conversely, levonorgestrel is approximately 98% bound to plasma proteins and is bound to both albumin and SHBG.Norgestimate is extensively metabolized into its active metabolites during first-pass metabolism in the liver and intestines. The major metabolite of norgestimate is norelgestromin and is formed from norgestimate via deacetylation in the liver and intestines. A more minor metabolite of norgestimate is levonorgestrel, which accounts for 20 to 25% (22 ± 6%) of an administered dose or about 40 to 70 µg norgestimate, and a very minor metabolite of norgestimate is levonorgestrel 17β-acetate. Both of these metabolites are active similarly to norgelstromin. With a typical oral contraceptive dosage of norgestimate of 200 to 250 µg/day, an amount of 50 to 60 µg/day levonorgestrel may be produced. This is similar to the ovulation-inhibiting dosage of levonorgestrel, and suggests that norgestimate may act in considerable part as a prodrug specifically of levonorgestrel. Following their formation, the active metabolites of norgestimate are inactivated via reduction, hydroxylation, and conjugation into levonorgestrel metabolites. The terminal half-life of norelgestromin is between 17 and 37 hours and of levonorgestrel is between 24 and 32 hours. The metabolites of norgestimate are eliminated 47% in urine and 37% in feces. Unchanged norgestimate is undetectable in urine.

Chemistry
Norgestimate, also known as 17α-ethynyl-18-methyl-19-nortestosterone 3-oxime 17β-acetate or as 17α-ethynyl-18-methylestr-4-en-17β-ol-3-one 3-oxime 17β-acetate, is a synthetic estrane steroid and a derivative of testosterone.  It is a racemic mixture of E and Z isomers. Norgestimate is more specifically a derivative of norethisterone (17α-ethynyl-19-nortestosterone) and is a member of the gonane (18-methylestrane) subgroup of the 19-nortestosterone family of progestins. It is the C3 oxime and C17β acetate ester of levonorgestrel and is also known as levonorgestrel acetate oxime. A related compound is norethisterone acetate oxime (norethisterone-3-oxime 17β-acetate).

History
Norgestimate was introduced as a component of combined oral contraceptives in 1986. Based on its year of introduction, norgestimate is sometimes described as a "third-generation" progestin. Norgestimate was approved in combination with estradiol for use in menopausal hormone therapy in 1999 in the United States, and a generic version of this preparation became available in this country in 2005.

Society and culture
Generic names
Norgestimate is the generic name of the drug and its INN, USAN, USP, BAN, and DCF. It is also known by its developmental code name ORF-10131.

Brand names
Norgestimate is marketed in combination with ethinylestradiol as a birth control pill under the brand names Amicette, Cilest, Cyclen, Edelsin, Effiprev, Estarylla, MonoNessa, Orlon, Ortho Tri-Cyclen, Ortho Tri-Cyclen Lo, Ortho-Cyclen, Pramino, Previfem, Sprintec, Triafemi, TriCilest, Tri-Cyclen, Tri-Cyclen LO, Tridette, Tri-Estarylla, Tri-Linyah, TriNessa, Tri-Previfem, and Tri-Sprintec. It is marketed in combination with estradiol for menopausal hormone therapy under the brand name Prefest only.

Availability
Norgestimate in combination with ethinylestradiol is marketed widely throughout the world, including in the United States, Canada, the United Kingdom, Ireland, elsewhere throughout Europe, South Africa, Latin America, and Asia. It is not listed as being marketed in Australia, New Zealand, Japan, South Korea, China, India, or certain other countries. Unlike the combined birth control pills of norgestimate with ethinylestradiol, the combination of norgestimate with estradiol, sold under the brand name Prefest for menopausal hormone therapy, is reportedly only marketed currently in the United States and Brazil.

Research
A 2017 study found that norgestimate inhibits staphylococcal biofilm formation and resensitizes methicillin-resistant Staphylococcus aureus to β-lactam antibiotics. In contrast, norelgestromin showed much weaker activity, indicating that the acetyl group of norgestimate is important for the activity. It was suggested by the researchers that norgestimate may be a promising lead compound for the development of new antibiotics.

References
Further reading
Henzl MR (July 2001). "Norgestimate. From the laboratory to three clinical indications". J Reprod Med. 46 (7): 647–61. PMID 11499185.
Curran MP, Wagstaff AJ (2001). "Estradiol and norgestimate: a review of their combined use as hormone replacement therapy in postmenopausal women". Drugs Aging. 18 (11): 863–85. doi:10.2165/00002512-200118110-00007. PMID 11772126. S2CID 22720686.
Curran MP, Wagstaff AJ (2002). "Spotlight on estradiol and norgestimate as hormone replacement therapy in postmenopausal women". Treat Endocrinol. 1 (2): 127–9. doi:10.2165/00024677-200201020-00006. PMID 15765628 </s>


<s> [INST] <<SYS>> You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information. <</SYS>> What is Sulconazole and explain in detail? [/INST]  </s>


<s> [INST] <<SYS>> You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information. <</SYS>> What is Ferric maltol and explain in detail? [/INST] Ferric maltol, sold under the brand names Accrufer (US) and Feraccru (EU), is an iron containing medication for the treatment of adults with low iron stores. It is taken by mouth.

Contraindications
The drug is contraindicated in people with hereditary hemochromatosis and other kinds of iron overload, as well as those repeatedly receiving blood transfusions and are therefore also at risk of developing iron overload.

Side effects
The most common side effects are flatulence (in 5% of people taking the drug), diarrhea (4%), constipation (4%), stool color change (4%), nausea (3%), vomiting (3%), and abdominal discomfort, bloating and pain (1%). Ferric maltol may cause serious side effects including increased risk of inflammatory bowel disease flare and iron overload in the body.

Interactions
No systematic interaction studies with ferric maltol have been conducted. Food reduces its uptake from the gut, as do calcium and magnesium salts and tetracycline antibiotics. Conversely, iron inhibits the uptake of many drugs, such as bisphosphonates, tetracycline antibiotics, quinolone antibiotics, levothyroxin, and levodopa. Combining the drug with intravenous iron can result in fast release of iron into the blood, potentially leading to low blood pressure or even collapse.Dimercaprol in combination with iron is toxic for the kidneys. The antibiotic chloramphenicol interferes with incorporation of iron into red blood cells and with iron excretion. Furthermore, iron can reduce the blood pressure lowering effects of methyldopa.Maltol is metabolized by the enzyme UGT1A6. It is not known whether inhibitors of this enzyme increase maltol concentrations in the body.

Pharmacology
Mechanism of action
Ferric maltol acts as a source of iron, which is essential for oxygen transport in the blood and other processes in the human body.

Pharmacokinetics
The substance is a complex of iron with maltol, which is absorbed from the gut and then dissociates, releasing iron and maltol separately into the bloodstream </s>


<s> [INST] <<SYS>> You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information. <</SYS>> What is Eplerenone and explain in detail? [/INST] Eplerenone, sold under the brand name Inspra, is an aldosterone antagonist type of potassium-sparing diuretic that is used to treat chronic heart failure and high blood pressure, particularly for patients with resistant hypertension due to elevated aldosterone. It is a steroidal antimineralocorticoid of the spirolactone group and a selective aldosterone receptor antagonist (SARA). Eplerenone is more selective than spironolactone at the mineralocorticoid receptor relative to binding at androgen, progestogen, glucocorticoid, or estrogen receptors.

Medical uses
Heart failure
Eplerenone reduces risk of death in patients with heart failure, particularly in patients with recent myocardial infarction (heart attack).

Hypertension
Eplerenone lowers blood pressure in patients with primary hypertension. Eplerenone also reduces arterial stiffness and vascular endothelial dysfunction.For persons with resistant hypertension, eplerenone is safe and effective for reducing blood pressure, particularly in persons with resistant hypertension due to hyperaldosteronism.

Central serous chorioretinopathy
Eplerenone is often prescribed for people with central serous chorioretinopathy (CSC). However, the most recent and largest randomized controlled trial showed that eplerenone has no significant effect on chronic CSC.

Adverse effects
Common adverse drug reactions (ADRs) associated with the use of eplerenone include: hyperkalaemia, hypotension, dizziness, and reduced renal clearance. Eplerenone may have a lower incidence than spironolactone of sexual side effects such as feminization, gynecomastia, impotence, low sex drive and reduction of size of male genitalia. This is because other antimineralocorticoids have structural elements of the progesterone molecule, causing progestogenic and antiandrogenic outcomes. When considering taking these medicines, it is important to note the variations in their ability to offset the nongenomic effects of aldosterone.Currently, there is not enough evidence available from the randomized controlled trials on side effects of eplerenone to do a benefit versus risk assessment in people with primary hypertension.

Interactions
Eplerenone is primarily metabolized by the cytochrome P450 enzyme CYP3A4. Thus the potential exists for adverse drug interactions with other drugs that induce or inhibit CYP3A4. Specifically, the concomitant use of the CYP3A4 potent inhibitors ketoconazole and itraconazole is contraindicated. Other CYP3A4 inhibitors including erythromycin, saquinavir, and verapamil should be used with caution </s>


<s> [INST] <<SYS>> You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information. <</SYS>> What is Retinyl palmitate and explain in detail? [/INST]  </s>


<s> [INST] <<SYS>> You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information. <</SYS>> What is Phenytoin and explain in detail? [/INST] Phenytoin (PHT), sold under the brand name Dilantin among others, is an anti-seizure medication. It is useful for the prevention of tonic-clonic seizures (also known as grand mal seizures) and focal seizures, but not absence seizures. The intravenous form, fosphenytoin, is used for status epilepticus that does not improve with benzodiazepines.  It may also be used for certain heart arrhythmias or neuropathic pain. It can be taken intravenously or by mouth. The intravenous form generally begins working within 30 minutes and is effective for roughly 24 hours. Blood levels can be measured to determine the proper dose.Common side effects include nausea, stomach pain, loss of appetite, poor coordination, increased hair growth, and enlargement of the gums. Potentially serious side effects include sleepiness, self harm, liver problems, bone marrow suppression, low blood pressure, and toxic epidermal necrolysis. There is evidence that use during pregnancy results in abnormalities in the baby.  It appears to be safe to use when breastfeeding. Alcohol may interfere with the medications effects.Phenytoin was first made in 1908 by the German chemist Heinrich Biltz and found useful for seizures in 1936. It is on the World Health Organizations List of Essential Medicines. Phenytoin is available as a generic medication.  In 2017, it was the 221st most commonly prescribed medication in the United States, with more than two million prescriptions.

Medical uses
Seizures
Tonic-clonic seizures: Mainly used in the prophylactic management of tonic-clonic seizures with complex symptomatology (psychomotor seizures). A period of 5–10 days of dosing may be required to achieve anticonvulsant effects.
Focal seizures: Mainly used to protect against the development of focal seizures with complex symptomatology (psychomotor and temporal lobe seizures). Also effective in controlling focal seizures with autonomic symptoms.
Absence seizures: Not used in treatment of pure absence seizures due to risk for increasing frequency of seizures. However, can be used in combination with other anticonvulsants during combined absence and tonic-clonic seizures.
Seizures during surgery: A 2018 meta-analysis found that early antiepileptic treatment with either phenytoin or phenobarbital reduced the risk of seizure in the first week after neurosurgery for brain tumors.
Status epilepticus: Considered after failed treatment using a benzodiazepine due to slow onset of action.

Other
Abnormal heart rhythms: may be used in the treatment of ventricular tachycardia and sudden episodes of atrial tachycardia after other antiarrhythmic medications or cardioversion has failed.  It is a class 1b antiarrhythmic.
Digoxin toxicity: Intravenous formulation is drug of choice for arrhythmias caused by cardiac glycoside toxicity.
Trigeminal neuralgia: Second choice drug to carbamazepine.

Special considerations
Phenytoin has a narrow therapeutic index. Its therapeutic range for an anticonvulsant effect is 10–20 μg/mL and for an antiarrhythmic effect 10–20 μg/mL.
The most common cause of phenytoin intoxication is self‑medication, which accounts for more than thirty percent of the cases.
Avoid giving intramuscular formulation unless necessary due to skin cell death and local tissue destruction.
Elderly patients may show earlier signs of toxicity.
In the obese, ideal body weight should be used for dosing calculations.
Pregnancy: Pregnancy category D due to risk of fetal hydantoin syndrome and fetal bleeding. However, optimal seizure control is very important during pregnancy so drug may be continued if benefits outweigh the risks. Due to decreased drug concentrations as a result of plasma volume expansion during pregnancy, dose of phenytoin may need to be increased if only option for seizure control.
Breastfeeding: The manufacturer does not recommend breastfeeding since low concentrations of phenytoin are excreted in breast milk.
Liver disease: Do not use oral loading dose. Consider using decreased maintenance dose.
Kidney disease: Do not use oral loading dose. Can begin with standard maintenance dose and adjust as needed.
Intravenous use is contraindicated in patients with sinus bradycardia, sinoatrial block, second- or third-degree atrioventricular block, Stokes-Adams syndrome, or hypersensitivity to phenytoin, other hydantoins or any ingredient in the respective formulation.

Side effects
Common side effects include nausea, stomach pain, loss of appetite, poor coordination, increased hair growth, and enlargement of the gums. Potentially serious side effects include sleepiness, self harm, liver problems, bone marrow suppression, low blood pressure, and toxic epidermal necrolysis. There is evidence that use during pregnancy results in abnormalities in the baby. Its use appears to be safe during breastfeeding. Alcohol may interfere with the medications effects.

Heart and blood vessels
Severe low blood pressure and abnormal heart rhythms can be seen with rapid infusion of IV phenytoin. IV infusion should not exceed 50 mg/min in adults or 1–3 mg/kg/min (or 50 mg/min, whichever is slower) in children. Heart monitoring should occur during and after IV infusion. Due to these risks, oral phenytoin should be used if possible.

Neurological
At therapeutic doses, phenytoin may produce nystagmus on lateral gaze. At toxic doses, patients experience vertical nystagmus, double vision, sedation, slurred speech, cerebellar ataxia, and tremor. If phenytoin is stopped abruptly, this may result in increased seizure frequency, including status epilepticus.Phenytoin may accumulate in the cerebral cortex over long periods of time which can cause atrophy of the cerebellum. The degree of atrophy is related to the duration of phenytoin treatment and is not related to dosage of the medication.Phenytoin is known to be a causal factor in the development of peripheral neuropathy.

Blood
Folate is present in food in a polyglutamate form, which is then converted into monoglutamates by intestinal conjugase to be absorbed by the jejunum. Phenytoin acts by inhibiting this enzyme, thereby causing folate deficiency, and thus megaloblastic anemia.
Other side effects may include: agranulocytosis, aplastic anemia, decreased white blood cell count, and a low platelet count.

Pregnancy
Phenytoin is a known teratogen, since children exposed to phenytoin are at a higher risk of birth defects than children born to women without epilepsy and to women with untreated epilepsy. The birth defects, which occur in approximately 6% of exposed children, include neural tube defects, heart defects and craniofacial abnormalities, including broad nasal bridge, cleft lip and palate, and smaller than normal head. The effect on IQ cannot be determined as no study involves phenytoin as monotherapy, however poorer language abilities and delayed motor development may have been associated with maternal use of phenytoin during pregnancy. This syndrome resembles the well-described fetal alcohol syndrome and has been referred to as "fetal hydantoin syndrome". Some recommend avoiding polytherapy and maintaining the minimal dose possible during pregnancy, but acknowledge that current data fails to demonstrate a dose effect on the risk of birth defects. Data now being collected by the Epilepsy and Antiepileptic Drug Pregnancy Registry may one day answer this question definitively.

Cancer
There is no good evidence to suggest that phenytoin is a human carcinogen.

Mouth
Phenytoin has been associated with drug-induced gingival enlargement (overgrowth of the gums), probably due to above-mentioned folate deficiency; indeed, evidence from a randomized controlled trial suggests that folic acid supplementation can prevent gingival enlargement in children who take phenytoin. Plasma concentrations needed to induce gingival lesions have not been clearly defined.  Effects consist of the following: bleeding upon probing, increased gingival exudate, pronounced gingival inflammatory response to plaque levels, associated in some instances with bone loss but without tooth detachment.

Skin
Hypertrichosis, Stevens–Johnson syndrome, purple glove syndrome, rash, exfoliative dermatitis, itching, excessive hairiness, and coarsening of facial features can be seen in those taking phenytoin.
Phenytoin therapy has been linked to the life-threatening skin reactions Stevens–Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). These conditions are significantly more common in patients with a particular HLA-B allele, HLA-B*1502. This allele occurs almost exclusively in patients with ancestry across broad areas of Asia, including South Asian Indians.
Phenytoin is primarily metabolized to its inactive form by the enzyme CYP2C9. Variations within the CYP2C9 gene that result in decreased enzymatic activity have been associated with increased phenytoin concentrations, as well as reports of drug toxicities due to these increased concentrations. The U.S. Food and Drug Administration (FDA) notes on the phenytoin drug label that since strong evidence exists linking HLA-B*1502 with the risk of developing SJS or TEN in patients taking carbamazepine, consideration should be given to avoiding phenytoin as an alternative to carbamazepine in patients carrying this allele.

Immune system
Phenytoin has been known to cause drug-induced lupus.Phenytoin is also associated with induction of reversible IgA deficiency.

Psychological
Phenytoin may increase risk of suicidal thoughts or behavior. People on phenytoin should be monitored for any changes in mood, the development or worsening depression, and/or any thoughts or behavior of suicide. Some case reports of acute phenytoin psychosis were already described.

Bones
Chronic phenytoin use has been associated with decreased bone density and increased bone fractures. Phenytoin induces metabolizing enzymes in the liver. This leads to increased metabolism of vitamin D, thus decreased vitamin D levels. Vitamin D deficiency, as well as low calcium and phosphate in the blood cause decreased bone mineral density.

Interactions
Phenytoin is an inducer of the CYP3A4 and CYP2C9 families of the P450 enzyme responsible for the livers degradation of various drugs.A 1981 study by the National Institutes of Health showed that antacids administered concomitantly with phenytoin "altered not only the extent of absorption but also appeared to alter the rate of absorption.  Antacids administered in a peptic ulcer regimen may decrease the AUC of a single dose of phenytoin. Patients should be cautioned against concomitant use of antacids and phenytoin."Warfarin and trimethoprim increase serum phenytoin levels and prolong the serum half-life of phenytoin by inhibiting its metabolism. Consider using other options if possible.

Pharmacology
Mechanism of action
Phenytoin is believed to protect against seizures by causing voltage-dependent block of voltage gated sodium channels. This blocks sustained high frequency repetitive firing of action potentials. This is accomplished by reducing the amplitude of sodium-dependent action potentials through enhancing steady-state inactivation. Sodium channels exist in three main conformations: the resting state, the open state, and the inactive state.
Phenytoin binds preferentially to the inactive form of the sodium channel. Because it takes time for the bound drug to dissociate from the inactive channel, there is a time-dependent block of the channel. Since the fraction of inactive channels is increased by membrane depolarization as well as by repetitive firing, the binding to the inactive state by phenytoin sodium can produce voltage-dependent, use-dependent and time-dependent block of sodium-dependent action potentials.The primary site of action appears to be the motor cortex where spread of seizure activity is inhibited. Possibly by promoting sodium efflux from neurons, phenytoin tends to stabilize the threshold against hyperexcitability caused by excessive stimulation or environmental changes capable of reducing membrane sodium gradient. This includes the reduction of post-tetanic potentiation at synapses which prevents cortical seizure foci from detonating adjacent cortical areas. Phenytoin reduces the maximal activity of brain stem centers responsible for the tonic phase of generalized tonic-clonic seizures.

Pharmacokinetics
Phenytoin elimination kinetics show mixed-order, non-linear elimination behaviour at therapeutic concentrations. Where phenytoin is at low concentration it is cleared by first order kinetics, and at high concentrations by zero order kinetics. A small increase in dose may lead to a large increase in drug concentration as elimination becomes saturated. The time to reach steady state is often longer than 2 weeks.

History
Phenytoin (diphenylhydantoin) was first synthesized by German chemist Heinrich Biltz in 1908.
Biltz sold his discovery to Parke-Davis, which did not find an immediate use for it. In 1938, outside people including H. Houston Merritt and Tracy Putnam discovered phenytoins usefulness for controlling seizures, without the sedative effects associated with phenobarbital.
According to Goodman and Gilmans Pharmacological Basis of Therapeutics:

In contrast to the earlier accidental discovery of the antiseizure properties of potassium bromide and phenobarbital, phenytoin was the product of a search among nonsedative structural relatives of phenobarbital for agents capable of suppressing electroshock convulsions in laboratory animals.
It was approved by the FDA in 1953 for use in seizures.
Jack Dreyfus, founder of the Dreyfus Fund, became a major proponent of phenytoin as a means to control nervousness and depression when he received a prescription for Dilantin in 1966. He has claimed to have supplied large amounts of the drug to Richard Nixon throughout the late 1960s and early 1970s, although this is disputed by former White House aides and Presidential historians.
Dreyfus experience with phenytoin is outlined in his book, A Remarkable Medicine Has Been Overlooked. Despite more than $70 million in personal financing, his push to see phenytoin evaluated for alternative uses has had little lasting effect on the medical community.  This was partially because Parke-Davis was reluctant to invest in a drug nearing the end of its patent life, and partially due to mixed results from various studies.
In 2008, the drug was put on the FDAs Potential Signals of Serious Risks List to be further evaluated for approval. The list identifies medications that the FDA has identified a potential safety issue, but does not mean that FDA has identified a causal relationship between the drug and the listed risk. To address this concern, the Warnings and Precautions section of the labeling for Dilantin injection was updated to include additional information about purple glove syndrome in November 2011.

Society and culture
Economics
Phenytoin is available as a generic medication.Since September 2012, the marketing licence in the UK has been held by Flynn Pharma Ltd, of Dublin, Ireland, and the product, although identical, has been called Phenytoin Sodium xxmg Flynn Hard Capsules. (The xxmg in the name refers to the strength—for example "Phenytoin sodium 25 mg Flynn Hard Capsules").  The capsules are still made by Pfizers Goedecke subsidiarys plant in Freiburg, Germany and they still have Epanutin printed on them. After Pfizers sale of the UK marketing licence to Flynn Pharma, the price of a 28-pack of 25 mg phenytoin sodium capsules marked Epanutin rose from 66p (about $0.88) to £15.74 (about $25.06). Capsules of other strengths also went up in price by the same factor—2,384%, costing the UKs National Health Service an extra £43 million (about $68.44 million) a year.  The companies were referred to the Competition and Markets Authority (CMA) who found that they had exploited their dominant position in the market to charge "excessive and unfair" prices.The CMA imposed a record £84.2 million fine on the manufacturer Pfizer, and a £5.2 million fine on the distributor Flynn Pharma and ordered the companies to reduce their prices.

Trade names
Phenytoin is marketed under many brand names worldwide.

Research
Tentative evidence suggests that topical phenytoin is useful in wound healing in people with chronic skin wounds. A meta-analysis also supported the use of phenytoin in managing various ulcers.Some clinical trials have explored whether phenytoin can be used as neuroprotector in multiple sclerosis.

References
Further reading
Dean L (2016) </s>


<s> [INST] <<SYS>> You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information. <</SYS>> What is Phenylephrine and explain in detail? [/INST] Phenylephrine is a medication primarily used as a decongestant, to dilate the pupil, to increase blood pressure, and to relieve hemorrhoids. It was long maintained that when taken orally as a decongestant, it relieves nasal congestion due to colds and hay fever. Phenylephrine can be taken by mouth, as a nasal spray, given by injection into a vein or muscle, or applied to the skin.Common side effects when taken by mouth or injected include nausea, vomiting, headache, and anxiety. Use on hemorrhoids is generally well tolerated. Severe side effects may include a slow heart rate, intestinal ischemia, chest pain, kidney failure, and tissue death at the site of injection. It is unclear if use during pregnancy or breastfeeding is safe. Phenylephrine is a selective α1-adrenergic receptor agonist which results in the constriction of both arteries and veins.Phenylephrine was patented in 1927 and came into medical use in 1938. It is available as a generic medication. Unlike pseudoephedrine, abuse of phenylephrine is very uncommon.As of 2022, there is push back on the effectiveness of phenylephrine as a decongestant, often fused with the supposition that phenylephrine is coasting on its historical status within the Food and Drug Administrations regulatory sphere as an established substitute for the proven use of pseudoephedrine as a decongestant, whose availability has been restricted by law due to its use in the illicit synthesis of methamphetamine.

Medical uses
Decongestant
Phenylephrine is used as a decongestant sold as an oral medicine or as a nasal spray. It is a common ingredient in over-the-counter decongestants in the United States.Phenylephrine is used as an alternative for pseudoephedrine in decongestant medicines due to pseudoephedrines use in the illicit manufacture of methamphetamine. Its efficacy as an oral decongestant has been questioned, with several independent studies finding that it provided no more relief to sinus congestion than a placebo.A 2007 meta-analysis concluded that the evidence for its effectiveness is insufficient, though another meta-analysis published shortly thereafter by researchers from GlaxoSmithKline found the standard 10-mg dose to be more effective than a placebo; however, the fact that GSK markets many products containing phenylephrine has raised some speculation regarding selective publishing and other controversial techniques. A 2007 study by Wyeth Consumer Healthcare notes that 7 studies available in 1976 support the efficacy of phenylephrine at a 10 mg dosage.Two studies published in 2009, examined the effects of phenylephrine on symptoms of allergic rhinitis by exposing people to pollen in a controlled, indoor environment. Neither study was able to distinguish between the effects of phenylephrine or a placebo. Pseudoephedrine and loratadine–montelukast therapy were found to be significantly more effective than both phenylephrine and placebo.The Food and Drug Administration withdrew the indication "for the temporary relief of nasal congestion associated with sinusitis" in 2007.Pseudoephedrine was previously much more commonly available in the United States, however, provisions of the Combat Methamphetamine Epidemic Act of 2005 placed restrictions on the sale of pseudoephedrine products to prevent the clandestine manufacture of methamphetamine. Since 2004, phenylephrine has been increasingly marketed as a substitute for pseudoephedrine; some manufacturers have changed the active ingredients of products to avoid the restrictions on sales. Phenylephrine has been off patent for some time, and many generic brands are available.

Hemorrhoids
Hemorrhoids are caused by swollen veins in the rectal area. Phenylephrine can be used topically to prevent symptoms of hemorrhoids. Phenylephrine causes the constriction of vascular smooth muscle and is often used in the treatment of hemorrhoids presumably to narrow the swollen veins and relieve the attendant pain. However, veins—unlike arteries—contain less vascular smooth muscle in their walls so the mechanism by which pain relief is achieved is likely related to something other than vascular change alone. Products for treatment may also include substances that will form a protective barrier over the inflamed area, resulting in less pain when feces are passed.

Pupil dilation
Phenylephrine is used as an eye drop to dilate the pupil to facilitate visualization of the retina. It is often used in combination with tropicamide as a synergist when tropicamide alone is not sufficient. Narrow-angle glaucoma is a contraindication to phenylephrine use. As a mydriatic, it is available in 2.5% and 10% minims. Phenylephrine eye drops are applied to the eye after a topical anesthetic is applied.

Intraocular bleeding
Phenylephrine has been used as an intracameral injection into the anterior chamber of the eye to arrest intraocular bleeding occurring during cataract and glaucoma surgery.

Vasopressor
Phenylephrine is commonly used as a vasopressor to increase the blood pressure in unstable patients with hypotension, especially resulting from septic shock. Such use is common in anesthesia or critical-care practices; it is especially useful in counteracting the hypotensive effect of epidural and subarachnoid anesthetics, as well as the vasodilating effect of bacterial toxins and the inflammatory response in sepsis and systemic inflammatory response syndrome. The elimination half life of phenylephrine is about 2.5 to 3.0 hours. The clinical effects of a single intravenous bolus dose of phenylephrine are short lived and needs to be repeated every 10–15 minutes. Commonly the drug is given as a carefully titrated intravenous infusion with a syringe pump or volumetric pump.
Because of its vasoconstrictive effect, phenylephrine can cause severe necrosis if it infiltrates the surrounding tissues. Because of this, it should be given through a central line if at all possible. Damage may be prevented or mitigated by infiltrating the tissue with the alpha blocker phentolamine by subcutaneous injection.Phenylephrine hydrochloride at 0.25% is used as a vasoconstrictor in some suppository formulations.Recently, Phenylephrine has been used to treat conditions of orthostatic intolerance such as postural orthostatic tachycardia syndrome - where by activation of venous alpha 1 adrenoreceptors increases venous return and stroke volume which improves symptoms.

Priapism
Phenylephrine is used to treat priapism. It is diluted with normal saline and injected directly into the corpora cavernosa. The mechanism of action is to cause constriction of the blood vessels entering into the penis, thus causing decreased blood flow and relieving the priapism. An injection is given every 3–5 minutes. If priapism is not resolved in one hour, another form of therapy is considered.

Side effects
Phenylephrine may cause side effects such as headache, reflex bradycardia, excitability, restlessness and cardiac arrhythmias. Phenylephrine is not suggested for use in people with hypertension.

Heart
The primary side effect of phenylephrine is high blood pressure. People with high blood pressure are typically advised to avoid products containing it. Because this medication is a sympathomimetic amine without beta-adrenergic activity, it does not increase contractility force and output of the cardiac muscle. It may increase blood pressure resulting in a slow heart rate through stimulation of vascular (likely carotid) baroreceptors. A common side effect during IV administration is reflex bradycardia. The low concentration eye drops do not cause blood pressure changes and the changes with the higher dose drops do not last long.

Other
Prostatic hyperplasia can also be worsened by use, and chronic use can lead to rebound hyperemia. People with a history of anxiety or panic disorders, or on anticonvulsant medication for epilepsy should not take this substance </s>


<s> [INST] <<SYS>> You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information. <</SYS>> What is Kaopectate and explain in detail? [/INST] Kaopectate is an orally taken medication from  Arcadia Consumer Healthcare for the treatment of mild diarrhea. It is also sometimes used to treat indigestion, nausea, and stomach ulcers. The active ingredients have varied over time, and are different between the United States and Canada. The original active ingredients were kaolinite and pectin. In the US, the active ingredient is now bismuth subsalicylate (the same as in Pepto-Bismol). In Switzerland, attapulgite is used.

Ingredients
The active ingredient in Kaopectate has changed since its original creation </s>


<s> [INST] <<SYS>> You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information. <</SYS>> What is Mifepristone and explain in detail? [/INST] Mifepristone, also known as RU-486, is a medication typically used in combination with misoprostol to bring about a medical abortion during pregnancy and manage early miscarriage. This combination is 97% effective during the first 63 days of pregnancy. It is also effective in the second trimester of pregnancy. Effectiveness should be verified two weeks after use. It is taken by mouth.Common side effects include abdominal pain, feeling tired, and vaginal bleeding. Serious side effects may include heavy vaginal bleeding, bacterial infection, and birth defects if the pregnancy does not end. If used, appropriate follow up care needs to be available. Mifepristone is an antiprogestogen. It works by blocking the effects of progesterone, making both the cervix and uterine vessels dilate and causing uterine contraction.Mifepristone was developed in 1980 and came into use in France in 1987. It became available in the United States in 2000. It is on the World Health Organizations List of Essential Medicines. Mifepristone was approved by Health Canada in 2015 and became available in Canada in January 2017. Cost and availability limits access in many parts of the developing world.

Medical uses
Abortion
Mifepristone followed by a prostaglandin analog (misoprostol or gemeprost) is used for medical abortion. Medical organizations have found this combination to be safe and effective. Guidelines from the Royal College of Obstetricians and Gynaecologists describe medication abortion using mifepristone and misoprostol as effective and appropriate at any gestational age. The World Health Organization and the American Congress of Obstetricians and Gynecologists recommend mifepristone followed by misoprostol for first- and second-trimester medical abortion. Mifepristone alone is less effective, resulting in abortion within 1–2 weeks in anywhere from 54% to 92% of pregnancies, according to review of 13 studies.

Cushings syndrome
Mifepristone is used for the medical treatment of high blood sugar caused by high cortisol levels in the blood (hypercortisolism) in adults with endogenous Cushings syndrome who also have type 2 diabetes mellitus or glucose intolerance and have failed surgery or cannot have surgery.

Other
Mifepristone at low doses has been used for emergency contraception. It may also be used together with misoprostol for early pregnancy loss. Mifepristone has also been used to treat symptomatic leiomyoma (uterine fibroids) and endometriosis.

Side effects
Serious complications with mifepristone are rare with about 0.04%–0.9% requiring hospitalization and 0.05% requiring blood transfusion.Nearly all women using the mifepristone/misoprostol regimen experienced abdominal pain, uterine cramping, and vaginal bleeding or spotting for an average of 9–16 days. For most women, the most severe cramps after use of misoprostol last for less than 6 hours and can generally be managed with ibuprofen. Up to 8% of women experienced some type of bleeding for 30 days or more. Other less common side effects included nausea, vomiting, diarrhea, dizziness, fatigue, and fever. Pelvic inflammatory disease is a very rare but serious complication. Excessive bleeding and incomplete termination of a pregnancy require further intervention by a doctor (such as a repeat dose of misoprostol or a vacuum aspiration). Mifepristone is contraindicated in the presence of adrenal failure, long-term oral corticosteroid therapy (although inhaled and topical steroids are fine), hemorrhagic disorders, inherited porphyria, and hemophilia or anticoagulant use. Women with an intrauterine device in their uterus should remove the IUD prior to medication abortion to avoid unnecessary cramping. Mifepristone is not effective in treating ectopic pregnancy.
A postmarketing summary found, of about 1.52 million women who had received mifepristone until April 2011 in the United States, 14 were reported to have died after application. Eight of these cases were associated with sepsis; the other six had various causes such as drug abuse and suspected murder. Other incidents reported to the FDA included 612 nonlethal hospitalizations, 339 blood transfusions, 48 severe infections, and 2,207 (0.15%) adverse events altogether.

Cancer
No long-term studies to evaluate the carcinogenic potential of mifepristone have been performed. This is in accord with ICH guidelines, which do not require carcinogenicity testing in nongenotoxic drugs intended for administration for less than six months.

Pregnancy
Mifepristone alone results in abortion within 1–2 weeks in 54% to 92% of pregnancies.  The effectiveness increases to greater than 90% if misoprostol is given after the mifepristone. There is no evidence that the effects of mifepristone can be reversed, although some anti-abortion groups claim that it can be reversed by giving progesterone. Researchers in the United States initiated a trial of the so-called "reversal" regimen in 2019, but stopped prematurely due to serious safety concerns about using mifepristone without follow-up misoprostol. Giving progesterone has not been shown to halt medication abortion, and not completing the combination regimen of mifepristone and misoprostol may cause serious bleeding.In those who continue pregnancy after use of mifepristone together with misoprostol for termination, birth defects may occur. Exposure to a single large dose of mifepristone in newborn rats was not associated with any reproductive problems, although chronic low-dose exposure of newborn rats to mifepristone was associated with structural and functional reproductive abnormalities. Studies in mice, rats, and rabbits revealed developmental abnormalities for rabbits, but not rats or mice.

Pharmacology
Pharmacodynamics
Mifepristone is a steroidal antiprogestogen (IC50 = 0.025 nM for the PR), as well as an antiglucocorticoid (IC50 = 2.2 nM for the GR) and antiandrogen (IC50 = 10 nM for the AR) to a much lesser extent. It antagonizes cortisol action competitively at the receptor level.In the presence of progesterone, mifepristone acts as a competitive progesterone receptor antagonist (in the absence of progesterone, mifepristone acts as a partial agonist). Mifepristone is a 19-nor steroid with a bulky p-(dimethylamino) phenyl substituent above the plane of the molecule at the 11β-position responsible for inducing or stabilizing an inactive receptor conformation and a hydrophobic 1-propynyl substituent below the plane of the molecule at the 17α-position that increases its progesterone receptor binding affinity.In addition to being an antiprogestogen, mifepristone is also an antiglucocorticoid and a weak antiandrogen. Mifepristones relative binding affinity at the progesterone receptor is more than twice that of progesterone, its relative binding affinity at the glucocorticoid receptor is more than three times that of dexamethasone and more than ten times that of cortisol. Its relative binding affinity at the androgen receptor is less than one-third that of testosterone, and it does not bind to the estrogen receptor or the mineralocorticoid receptor.Mifepristone as a regular contraceptive at 2 mg daily prevents ovulation (1 mg daily does not). A single preovulatory 10-mg dose of mifepristone delays ovulation by three to four days and is as effective an emergency contraceptive as a single 1.5-mg dose of the progestin levonorgestrel.In women, mifepristone at doses greater or equal to 1 mg/kg antagonizes the endometrial and myometrial effects of progesterone. In humans, an antiglucocorticoid effect of mifepristone is manifested at doses greater or equal to 4.5 mg/kg by a compensatory increase in ACTH and cortisol. In animals, a weak antiandrogenic effect is seen with prolonged administration of very high doses of 10 to 100 mg/kg.In medication abortion regimens, mifepristone blockade of progesterone receptors directly causes endometrial decidual degeneration, cervical softening and dilatation, release of endogenous prostaglandins, and an increase in the sensitivity of the myometrium to the contractile effects of prostaglandins. Mifepristone-induced decidual breakdown indirectly leads to trophoblast detachment, resulting in decreased syncytiotrophoblast production of hCG, which in turn causes decreased production of progesterone by the corpus luteum (pregnancy is dependent on progesterone production by the corpus luteum through the first nine weeks of gestation—until placental progesterone production has increased enough to take the place of corpus luteum progesterone production). When followed sequentially by a prostaglandin, mifepristone 200 mg is (100 mg may be, but 50 mg is not) as effective as 600 mg in producing a medical abortion.Contragestion is a term promoted by Étienne-Émile Baulieu in the context of his advocacy of mifepristone, defining it as inclusive of some hypothesized mechanisms of action of some contraceptives and those of mifepristone to induce abortion. Baulieus definition of a contragestive included any birth control method that could possibly act after fertilization and before nine-weeks gestational age.

Pharmacokinetics
The elimination half-life is complex; according to the label: "After a distribution phase, elimination is at first slow, the concentration decreasing by a half between about 12 and 72 hours, and then more rapid, giving an elimination half-life of 18 hours. With radio receptor assay techniques, the terminal half-life is of up to 90 hours, including all metabolites of mifepristone able to bind to progesterone receptors." Metapristone is the major metabolite of mifepristone.

Chemistry
Mifepristone, also known as 11β-(4-(dimethylamino)phenyl)-17α-(1-propynyl)estra-4,9-dien-17β-ol-3-one, is a synthetic estrane steroid and a derivative of steroid hormones like progesterone, cortisol, and testosterone. It has substitutions at the C11β and C17α positions and double bonds at the C4(5) and C9(10) positions.

History
1980–1987
In April 1980, as part of a formal research project at the French pharmaceutical company Roussel-Uclaf for the development of glucocorticoid receptor antagonists, endocrinologist Étienne-Émile Baulieu and chemist Georges Teutsch synthesized mifepristone (RU-38486, the 38,486th compound synthesized by Roussel-Uclaf from 1949 to 1980; shortened to RU-486), which was discovered to also be a progesterone receptor antagonist. In October 1981, Étienne-Émile Baulieu, a consultant to Roussel-Uclaf, arranged tests of its use for medical abortion in 11 women in Switzerland by gynecologist Walter Herrmann at the University of Genevas Cantonal Hospital, with successful results announced on 19 April 1982. On 9 October 1987, following worldwide clinical trials in 20,000 women of mifepristone with a prostaglandin analogue (initially sulprostone or gemeprost, later misoprostol) for medical abortion, Roussel-Uclaf sought approval in France for their use for medical abortion, with approval announced on 23 September 1988.

1988–1990
On 21 October 1988, in response to antiabortion protests and concerns of majority (54.5%) owner Hoechst AG of Germany, Roussel-Uclafs executives and board of directors voted 16 to 4 to stop distribution of mifepristone, which they announced on 26 October 1988. Two days later, the French government ordered Roussel-Uclaf to distribute mifepristone in the interests of public health. French Health Minister Claude Évin explained: "I could not permit the abortion debate to deprive women of a product that represents medical progress. From the moment Government approval for the drug was granted, RU-486 became the moral property of women, not just the property of a drug company." Following use by 34,000 women in France from April 1988 to February 1990 of mifepristone distributed free of charge, Roussel-Uclaf began selling Mifegyne (mifepristone) to hospitals in France in February 1990 at a price (negotiated with the French government) of US$48 (equivalent to $99.56 in 2021) per 600-mg dose.Aside from "did not want to get in the middle of the national battle over abortion" in the United States, Hoechst had another reason cited by The New York Post: "During World War II, Hoechst was called I.G. Farben, the firm that manufactured" the poison gas that killed so many in the concentration camps.

1991–1996
Mifegyne was subsequently approved in Great Britain on 1 July 1991, and in Sweden in September 1992, but until his retirement in late April 1994, Hoechst AG chairman Wolfgang Hilger, a devout Roman Catholic, blocked any further expansion in availability. On 16 May 1994, Roussel-Uclaf announced it was donating without remuneration all rights for medical uses of mifepristone in the United States to the Population Council, which subsequently licensed mifepristone to Danco Laboratories, a new single-product company immune to antiabortion boycotts, which won FDA approval as Mifeprex on 28 September 2000.

1997–1999
On 8 April 1997, after buying the remaining 43.5% of Roussel-Uclaf stock in early 1997, Hoechst AG (US$30 (equivalent to $51.83 in 2021) billion annual revenue) announced the end of its manufacture and sale of Mifegyne (US$3.44 (equivalent to $5.94 in 2021) million annual revenue) and the transfer of all rights for medical uses of mifepristone outside of the United States to Exelgyn S.A., a new single-product company immune to antiabortion boycotts, whose CEO was former Roussel-Uclaf CEO Édouard Sakiz. In 1999, Exelgyn won approval of Mifegyne in 11 additional countries, and in 28 more countries over the following decade.

Society and culture
Mifepristone is on the World Health Organizations List of Essential Medicines. Since 2019 it has been included on the core list, with misoprostol, with a special note "where permitted under national law and where culturally acceptable".

Frequency of use
United States
Medication abortions voluntarily reported by 33 U.S. states to the Centers for Disease Control and Prevention (CDC) have increased as a percentage of total abortions every year since the approval of mifepristone: 1.0% in 2000, 2.9% in 2001, 5.2% in 2002, 7.9% in 2003, 9.3% in 2004, 9.9% in 2005, 10.6% in 2006, and 13.1% in 2007 (20.3% of those at less than 9 weeks gestation).A Guttmacher Institute survey of abortion providers estimated that medication abortions accounted for 17% of all abortions and slightly over 25% of abortions before 9 weeks gestation in the United States in 2008 (94% of nonhospital medication abortions used mifepristone and misoprostol, 6% used methotrexate and misoprostol). Medication abortions accounted for 32% of first trimester abortions at Planned Parenthood clinics in the United States in 2008. Considering abortions performed in non-hospital facilities, medication abortions accounted for 24% in 2011 and 31% in 2014. In 2014, facilities that provided a relatively small number of abortions (fewer than 400 procedures per year) were more likely to perform them with medication. Medication abortions accounted for 39% of all U.S. abortions in 2017, and 54% in 2020.

Europe
In France, the percentage of medication abortions of all abortions continues to increase: 38% in 2003, 42% in 2004, 44% in 2005, 46% in 2006, 49% in 2007 (vs. 18% in 1996). In England and Wales, 52% of early abortions (less than 9 weeks gestation) in 2009 were medication-based; the percentage of all abortions that are medication-based has increased every year for the past 14 years (from 5% in 1995 to 40% in 2009) and has more than doubled in the last five years. In Scotland, 81.2% of early abortions in 2009 were medication-based (up from 55.8% in 1992 when medication abortion was introduced); the percentage of all abortions that are medication-based has increased every year for the past 17 years (from 16.4% in 1992 to 69.9% in 2009). In Sweden, 85.6% of early abortions and 73.2% of abortions before the end of the 12th week of gestation in 2009 were medication-based; 68.2% of all abortions in 2009 were medication-based. In Great Britain and Sweden, mifepristone is licensed for use with vaginal gemeprost or oral misoprostol. As of 2000, more than 620,000 women in Europe had had medication abortions using a mifepristone regimen. In Denmark, mifepristone was used in between 3,000 and 4,000 of just over 15,000 abortions in 2005.

Legal status
United States
Mifepristone was approved for abortion in the United States by the FDA in September 2000. It is legal and available in all 50 states, Washington, D.C., Guam, and Puerto Rico. It is a prescription drug, but was not initially available to the public through pharmacies; its distribution is primarily restricted to specially qualified licensed physicians, sold by Danco Laboratories under the trade name Mifeprex. As of September 2021, in 32 states, the drug could only be provided by a licensed physician, and in 19 states, the prescribing clinician was required to be physically in the room with the patient while they are taking the drug.Roussel Uclaf did not seek U.S. approval, so in the United States legal availability was not initially possible. The United States banned importation of mifepristone for personal use in 1989, a decision supported by Roussel Uclaf. In 1994, Roussel Uclaf gave the U.S. drug rights to the Population Council in exchange for immunity from any product liability claims. The Population Council sponsored clinical trials in the United States. The drug went on approvable status from 1996. Production was intended to begin through the Danco Group in 1996, but they withdrew briefly in 1997 due to a corrupt business partner, delaying availability again.In 2016, the US Food and Drug Administration approved mifepristone, to end a pregnancy through 70 days gestation (70 days or less since the first day of a womans last menstrual period). The approved dosing regimen is 200 mg of mifepristone taken by mouth (swallowed).  24 to 48 hours after taking mifepristone, 800 mcg (micrograms) of misoprostol is taken buccally (in the cheek pouch), at a location appropriate for the patient.Mifepristone tablets have a marketing authorization in the United States for the treatment of high blood sugar caused by high cortisol levels in the blood (hypercortisolism) in adults with endogenous Cushings syndrome who have type 2 diabetes mellitus or glucose intolerance and have failed surgery or cannot have surgery.In 2019, the first generic form of mifepristone in the United States became available, manufactured by GenBioPro.Due to the COVID-19 pandemic, safe access to mifepristone was a concern, and the American College of Obstetricians and Gynecologists among other groups filed a lawsuit to relax the FDAs rule as to allow mifepristone to be acquired from mail-order and retail pharmacies. While the Fourth Circuit had granted a preliminary injunction to allow this distribution, the Supreme Court of the United States issued a stay order in January 2021 to retain the FDAs rule pending the results of the ongoing litigation.On 16 December 2021, the FDA voluntarily adopted a new rule permanently relaxing the requirement that the pill be obtained in person, allowing it to be sent through the mail. A prescription is still required, so that a doctor can screen for risk factors that would make taking the pill unsafe for the mother.

Subsection H
Some drugs are approved by the FDA under subsection H, which has two subparts. The first sets forth ways to rush experimental drugs, such as aggressive HIV and cancer treatments, to market when speedy approval is deemed vital to the health of potential patients. The second part of subsection H applies to drugs that not only must meet restrictions for use due to safety requirements, but also are required to meet postmarketing surveillance to establish that the safety results shown in clinical trials are seconded by use in a much wider population. Until December 2021, Mifepristone was approved under the second part of subsection H. The result is that women could not pick the drug up at a pharmacy, but were required to receive it directly from a doctor. Due to the possibility of adverse reactions such as excessive bleeding, which may require a blood transfusion, and incomplete abortion, which may require surgical intervention, the drug was only considered safe if a physician who is capable of administering a blood transfusion or a surgical abortion is available to the patient in the event of such emergencies. The approval of mifepristone under subsection H included a black box warning.

Europe
Outside the United States, mifepristone is marketed and distributed by Exelgyn Laboratories under the tradename Mifegyne. It was approved for use in France in 1988 (initial marketing in 1989), the United Kingdom in 1991, Sweden in 1992, then Austria, Belgium, Denmark, Finland, Germany, Greece, Luxembourg, the Netherlands, Spain, and Switzerland in 1999. In 2000, it was approved in Norway, Russia and Ukraine. Serbia and Montenegro approved it in 2001, Belarus and Latvia in 2002, Estonia in 2003, Moldova in 2004, Albania and Hungary in 2005, Portugal in 2007,  Romania in 2008, Bulgaria, Czech Republic and Slovenia in 2013. In Italy, clinical trials have been constrained by protocols requiring women be hospitalized for three days, but the drug was finally approved on 30 July 2009 (officialized later in the year), despite strong opposition from the Vatican. In Italy, the pill must be prescribed and used in a clinical structure and is not sold at chemists. It was approved in Hungary in 2005, but as of 2005 had not been released on the market yet, and was the target of protests. Mifepristone is currently licensed in Ireland for use of abortions up to 12 weeks since it was legalised in 2018. Mifepristone is not available in Poland, where abortion is highly restricted.Mifepristone 200 mg tablets (Mifegyne, Mifepristone Linepharma, Medabon) have marketing authorizations in the European Economic Area from the European Medicines Agency (EMA) for:
Early first trimester medication abortion when followed by a prostaglandin analog (misoprostol or gemeprost) through 63 days gestational age
Second trimester medication abortion when followed by a prostaglandin analog
Cervical softening and dilation prior to first trimester surgical abortion
Induction of labor after fetal death in utero when prostaglandin analogs and oxytocin are contraindicated

Other countries
Mifepristone was banned in Australia in 1996. In late 2005, a private members bill was introduced to the Australian Senate to lift the ban and transfer the power of approval to the Therapeutic Goods Administration (TGA). The move caused much debate in the Australian media and among politicians. The bill passed the Senate on 10 February 2006, and mifepristone is now legal in Australia. It is provided regularly at several specialized abortion clinics per state. Mifepristone 200 mg tablets have marketing authorizations in Australia from the TGA for early first trimester medication abortion when followed by the prostaglandin analog misoprostol through 63 days gestational age and second trimester medication abortion when followed by a prostaglandin analog.In New Zealand, pro-abortion rights doctors established an import company, Istar, and submitted a request for approval to Medsafe, the New Zealand pharmaceutical regulatory agency. After a court case brought by Right to Life New Zealand failed, use of mifepristone was permitted.Mifepristone was approved in Israel in 1999.Clinical trials of mifepristone in China began in 1985. In October 1988, China became the first country in the world to approve mifepristone. Chinese organizations tried to purchase mifepristone from Roussel Uclaf, which refused to sell it to them, so in 1992 China began its own domestic production of mifepristone. In 2000, the cost of medication abortion with mifepristone was higher than surgical abortion and the percentage of medication abortions varied greatly, ranging from 30% to 70% in cities to being almost nonexistent in rural areas.
A report from the United States Embassy in Beijing in 2000 said mifepristone had been widely used in Chinese cities for about two years, and that according to press reports, a black market had developed with many women starting to buy it illegally (without a prescription) from private clinics and drugstores for about US$15 (equivalent to $23.6 in 2021), causing Chinese authorities to worry about medical complications from use without physician supervision.In 2001, mifepristone was approved in Taiwan. Vietnam included mifepristone in the National Reproductive Health program in 2002.Mifepristone is approved in only one sub-Saharan African country—South Africa, where it was approved in 2001. It is also approved in one north African country—Tunisia, also in 2001.Mifepristone was approved for use in India in 2002, where medication abortion is referred to as "medical termination of pregnancy". It is only available under medical supervision, not by prescription, due to adverse reactions such as excessive bleeding, and criminal penalties are given for buying or selling it on the black market or over-the-counter at pharmacies.medication abortion used to be available in Canada but on a limited basis using methotrexate and misoprostol. Clinical trials were done in 2000 in various Canadian cities comparing methotrexate to mifepristone, after approbation by the federal government. While both drugs had overall similar results, mifepristone was found to act faster. Health Canada gave approval to mifepristone in July 2015. Initially, its use was limited to seven weeks into a pregnancy, but this was changed to nine weeks in 2017. The previous requirement of written consent from the woman was also ended at the same time. It can be dispensed directly to a patient by a pharmacist or a prescribing health professional. Women are required to have an ultrasound to ensure the pregnancy is not ectopic.Mifepristone was registered for use in Azerbaijan, Georgia, and Uzbekistan in 2002, in Guyana and Moldova in 2004, in Mongolia in 2005, and in Armenia in 2007.Low dose mifepristone tablets (Bi Yun, Fu Nai Er, Hou Ding Nuo, Hua Dian, Si Mi An) for emergency contraception are available directly from a pharmacist without a prescription and with a prescription in China.Low dose mifepristone tablets for emergency contraception are available by prescription in Armenia (Gynepriston), Russia (Agesta, Gynepriston, Mifepristone 72, Negele), Ukraine (Gynepriston), and Vietnam (Mifestad 10, Ciel EC).

Controversy
Many anti-abortion groups in the United States actively campaigned against the approval of mifepristone and continue to actively campaign for its withdrawal </s>