|Other names||Phenethazinum, Phenethazine, Phenetazine; RP-3015, SC-1627, WY-1143|
|CompTox Dashboard (EPA)|
|Chemical and physical data|
|Molar mass||270.39 g·mol−1|
|3D model (JSmol)|
Fenethazine (INN) (brand names Anergen, Contralergial, Ethysine, Etisine, Lisergan, Lysergan; former developmental code names RP-3015, SC-1627, WY-1143), or phenethazine, is a first-generation antihistamine of the phenothiazine group. Promethazine, and subsequently chlorpromazine, were derived from fenethazine. Fenethazine, in turn, was derived from phenbenzamine.