Almost all AP showed a degree of weight gain after prolonged use, except for amisulpride, aripiprazole and ziprasidone, for which prolonged exposure resulted in negligible weight change.
Apparently Clozapine is the worst for weight gain, but people on here manage to lose weight on it somehow.
You could switch meds, but as you say it’s risky.
You could have a conversation with your psychiatrist about Metformin. That can help with weight loss on anti-psychotics.