The drug possessing antagonistic action at histamine, serotonin and muscarinic receptors is:
-Cyproheptadine blocks 5HT2A, H1 and muscarinic receptors. -It increases appetite and can be used to promote weight gain in children.
Promethazine
Terfenadine
Cyproheptadine
Hydroxyzine
Histamine, 5-HT and PGs