lemme guess-you're on neurontin. i'm not bipolar but it seems to be the panacea of modern meds. it does something GABA-related so they'll rx it for pain, epilepsy, anxiety, bipolar, etc and it's only approved as an anticonvulsant. sometimes i'll take 1/10 the max theraputic dose of seroquel to sleep and it's sure as fuck not an approved sleep med, but works great.

off-label stuff is just a matter of fda-approval. example=paxil's basically just another ssri but it's the only one "approved" for social anxiety disorder but i know my sister chooses to go with off-label stuff with longer half-lives most of the time.

if you fuck with the fda and start marketing stuff off-label, they'll fine you half a billion dollars, but approval takes years and more cash. so off-label stuff exists-even shit like zyban being more expensive than wellbutrin and considerably so b/c insurance companies pay for antidepressants before smoking-cessation drugs.