Perhaps she can try fasting? My boyfriend is on Olanzapine, he would sometimes fast to keep the weight off and it’s helped. I’m not schizophrenic nor am I on antipsychotics, but I do have a problem with binge eating - Irish sea moss has helped me with curbing my appetite ( especially my cravings for junk food ) and stops me from overeating, but take my advice with a pinch of salt.