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What Is Diphenhydramine Hci?

Diphenhydramine hydrochloride (HCL) is a type of generic prescription medication sold under a number of brand names in both over-the-counter and prescription forms. A type of antihistamine, doctors recommend the drug for the treatment of certain nasal conditions.

  1. Function

    • Diphenhydramine HCL works by preventing the actions of a chemical released by your immune system known as histamine. This chemical causes inflammation and triggers allergic responses to substances that your body perceives as a threat.

    Use

    • Diphenhydramine HCL helps relieve sneezing, a runny nose and itching eyes caused by hay fever or other allergies. Doctors also use the prescription form of the medication as a treatment for life-threatening reactions like anaphylaxis.

    Types

    • Diphenhydramine HCL is available as an oral medication in tablet, capsule and liquid formulations. The drug also comes in injectable and intravenous forms.

    Features

    • Drowsiness is a common side effect of diphenhydramine HCL, reports the U.S. National Library of Medicine, and because of this the drug is sometimes used as a sedative and as a treatment for insomnia, motion sickness and Parkinson's disease.

    Warning

    • Since it often causes drowsiness, avoid driving or operating heavy machinery while taking diphenhydramine HCL, cautions the U.S. National Library of Medicine. Also, refrain from drinking alcohol while taking the drug as this can cause excessive sedation.

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