What is Diphenhydramine hydrochloride - Meaning and definition

Published by Roberto Wenk. Last updated date: June 13, 2016.

The hydrochloride salt form of diphenhydramine, an ethanolamine and first-generation histamine antagonist with anti-allergic activity.
Diphenhydramine hydrochloride competitively blocks H1 receptors, thereby preventing the actions of histamine on bronchial smooth muscle, capillaries, and gastrointestinal (GI) smooth muscle. This prevents histamine-induced bronchoconstriction, vasodilation, increased capillary permeability, and GI smooth muscle spasms.

National Cancer Institute. NCI Drug Dictionary. Internet. September 15, 2009.

Published by Roberto Wenk. Last updated date: February 8, 2016.

Adult
PO
Allergic conditions, treatment and prophylaxis of motion sickness: 25-50 mg 3-4 times/day. Max: 300 mg/day.
Parkinson's disease. Initial: 25 mg tid, may increase to 50 mg 4 times/day.
Short-term management of insomnia 50 mg 30 min before bedtime.

IM/IV
Allergic conditions, treatment and prophylaxis of motion sickness, Parkinson's disease - 1% or 5% soln: 10-50 mg, up to 100 mg. Max: 400 mg/day.

Topical
Pruritic skin disorders - 1% or 2% cream/gel/soln/stick: apply to affected area up to 3-4 times/day.

Adverse drug reactions: extrasystoles, hypotension, tachycardia; confusion, dizziness, drowsiness, euphoria, excitement, fatigue, headache, insomnia, irritability, nervousness, GI disturbances, difficulty in micturition, urinary frequency, urinary retention.

Adapted from CIMS Drug Information System. Internet. Accessed on January 10, 2016.

To cite

Diphenhydramine hydrochloride. IAHPC Pallipedia. https://pallipedia.org/diphenhydramine-hydrochloride/. Accessed