Butorphanol

Butorphanol (Stadol) (INN) is a morphinan-type synthetic opioid analgesic developed by Bristol-Myers. Brand name Stadol was recently discontinued by the manufacturer. It is now only available in its generic formulations, manufactured by Novex, Mylan, Apotex and Ben Venue Laboratories. Butorphanol is most closely structurally related to levorphanol. Butorphanol is available only as butorphanol tartrate in injectable, tablet, and intranasal spray formulations.