meperidine + promethazine

Meperidine + promethazine is a fixed-dose combination drug product, most notably marketed under the brand name **Mepergan**. It consists of meperidine hydrochloride, a synthetic phenylpiperidine-derivative opioid agonist, and promethazine hydrochloride, a phenothiazine derivative with potent antihistaminic and sedative properties. Meperidine provides analgesia primarily through its action as an agonist at the mu-opioid receptor. Promethazine acts as a competitive H1 receptor antagonist and also exhibits anticholinergic and antiemetic effects, which help to potentiate the sedative effects of the opioid and mitigate opioid-induced nausea. The combination was historically indicated for the management of moderate to severe pain and as a preanesthetic medication to provide both analgesia and sedation. While the parenteral injection form received FDA approval, it is no longer actively marketed in the United States, and the oral capsule formulation was withdrawn after being found to lack substantial evidence of effectiveness.

Brand names

MeperganMepergan Fortis

Other names

meperidine hydrochloride + promethazine hydrochloride