I was prescribed an atypical antipsychotic* originally for bipolar disorder in my late teens. At the time, it was an absolute lifesaver. I had almost completely lost my ability to function, and the treatment brought me back to an operating state sufficient to complete high school without completely sinking my GPA.

I had to stop using it because of unacceptable side effects (rapid weight gain and sexual dysfunction), and it took me a long time to find something else that worked as well. The medication that ended up working for me was originally developed as an anticonvulsant. My symptoms lessened over time in adulthood, but if I hadn't had the course correction provided by repurposed 'Big Pharma' medications I would be living a much harder life.

*: I'm not naming medications because I don't want to promote them. What worked for me isn't necessarily what will work for anyone else.

Back when my doctor and I didn't know if I had true bipolar disorder vs. what seems to be "depression of a bipolar nature" (with my never going manic unless I'm taking a drug that triggers it), I was prescribed the atypical antipsychotic Zyprexa at full dosage, initially by my previous doctor, and also found its infamous side effects to be unacceptable. Tried another with that previous doctor and got orthostatic hypotension, then with this doctor tried an anticonvulsant, which I had to stop because of bad skin side effects (still have little bright red flecks on my skin here and there). At that point, especially with the very slow ramp up of the anticonvulsant (meaning for a long while I didn't have a therapeutic dose), we crossed our fingers and stopped trying mood stabilizers, which lead to the change in diagnosis. (Elsewhere in this topic I mention how I later started taking a low dose of another antipsychotic to deal with anxiety in general, with very useful side effects for insomnia and allergies.)

I did name one drug name because if any other atypical anti-psychotic will do the trick it should perhaps be tried, Zyprexa is pretty infamous for weight gain among other things.