<human>: So here's my dilemma.  I got sick, and spent most of the day in bed.  About an hour ago I had some weed, and started reading my store-brand cough & cold remedy bottle, wondering to myself what the active ingredient was.  It turns out the one that makes you fall asleep is doxylamine, which is 6.25mg/15ml.  There being 296mL in the bottle, we can assume 123.3mg of doxylamine in the entire bottle.   

I found the fatal dosage was "50-50,000 mg/kg", and was not sure what this meant.  I understand it is just parts-per notation, but I do not know how to convert between the two.  So, does anyone out there know how?  I know it's like 7:00 AM in the U.K. right now, anyone want some early morning math?

Can you condense the text into three sentences or less?
<bot>: Lethal dose is 50-5,000 mg/kg.  The bottle has 123 mg.  Will it kill me?