<human>: Can you give me the gist of the text in a nutshell?

I adopted Chester in August of 2009 from a shelter when he was 4 months old. At the time he was wearing a cone because of a bug bite on his head that he had scratched up (or so I was told).  Fast forward to today, he is still having to wear the cone because of repeated self-injury to his head (scratches till he bleeds and just keeps going, like he feels no pain).  I've been to the vet more times than I can count, spent ungodly amounts of money, ruled out all possible physical issues (parasites, fungus, mites, etc), and still no answers.  

He is currently on Atopica per vet recommendation, but after almost 6 weeks I haven't seen any improvement in his scratching.  He also bites his back toes to the point of bleeding.  He was previously on Gabapentin which helped for a few months and he didn't have to wear the cone, but then it stopped working.  He's also now wearing sweaters because he had a reaction to a flea med on his back, which he then scratched the heck out of and left a scar.  The only thing that keeps him from scratching the scar is wearing sweaters.

I really feel like this is a behavioral/OCD/self-injury issue, not a physical one.  Does anyone have any suggestions of other meds or anything??  Other than this issue, he is the sweetest lap kitty ever, always by my side, loves to play, gets along great with my other cat.  Thank you for reading, any suggestions are appreciated!!

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<bot>: My cat has been having to wear a cone for over 2 years because of self-injury to his head and toes. Tried almost everything to fix, any suggestions??