Phenergan® (promethazine hydrochloride) is a prescription medicine approved for the treatment of various conditions, including nausea and vomiting, motion sickness, and various types of allergies. But how exactly does Phenergan work?
Phenergan has several different effects in the body and the brain. Many of these effects are most likely due to its antihistamine activity, since the medication works by blocking histamine receptors.
It also belongs to a group of drugs 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 it is not used as an antipsychotic.
Phenergan also blocks acetylcholine receptors, which is probably why it helps to alleviate nausea and motion sickness.
(Click Phenergan for more information on how Phenergan works, to learn about the potential side effects of this medication, and to find out what you should discuss with your healthcare provider before starting treatment.)
Written by/reviewed by: Kristi Monson, PharmD;Arthur Schoenstadt, MD
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