Pharmacology C.N.S e866bf17 Weight gain caused by antipsychotics is due to antagonism of: A 5 HT3 B 5 HT2A C 5 HT2B D 5 HT2C High-Yield Explanation Ans. (D) 5HT2C (Ref: Goodman Gilman 12/e p435)Antipsychotics cause weight gain due to their antagonistic action on H1 and 5HT2C receptors.