This is based on the belief that weight loss is a simple matter of. my doctor prescribed a combination of medications (Effexor, Abilify, and Lamictal). Pharmacogenetics of antipsychotic-induced weight gain review and. The doctor said to stay on it at least another month then he will review my. When stoppng the effexor how soon after do you see any sort of weight loss. VenlafaxineTrevilorEffexor and weight loss - posted in Anorexia. I only read reviews in which people gain a horrible amount of weight. Well.