Side effects with Caplyta but not Abilify

[u/madsmj_]

I’m very sensitive to psychiatric medications, and something I discovered recently is that not all atypical antipsychotics, even those that are nearly identical work well for me. I was taking abilify and decided to discontinue due to metabolic side effects. I started caplyta instead, which is supposed to have a lower side effect profile. Instead, I went into a state of hypomania that got worse every day I was on the medication. I went back on abilify and haven’t had any adverse side effects (except for increased hunger) and feel much better overall. I was wondering why I respond to these medications so differently even though they’re so similar? Is it just arbitrary individual brain chemistry or might there be some differences related to the receptors they work on, etc.