hydrochloride) is a prescription medication approved for a variety of widely different uses. It is used most commonly as a nausea medication, although it is frequently used for other purposes as well.
It should be noted that this article applies only to Phenergan products that contain only promethazine as the active ingredient. Some cough syrups (such as Phenergan with Codeine) contain other active ingredients as well.
Who Makes This Medication?
Brand-name Phenergan tablets
, syrup, and suppositories were made by Wyeth Pharmaceuticals, Inc. but are no longer available. Brand-name Phenergan injection
is made by Baxter Healthcare Corporation. Generic versions are made by various manufacturers.
Phenergan has several different effects in the body and the brain. Many of the effects are most likely due to its antihistamine activity. This medicine works by blocking histamine receptors. It also belongs to a group of medications known as phenothiazines.
Although phenothiazines are usually used as antipsychotic
medications, Phenergan has little dopamine-blocking activity. This makes it a weak antipsychotic medication, and this drug is not used as an antipsychotic.
Phenergan also blocks acetylcholine receptors, which is probably why it helps to alleviate nausea and motion sickness.