OTC
Antihistamine (sedating)
Diphenhydramine Hydrochloride
Last reviewed April 2026
Who is this for?
What is this drug?
Diphenhydramine is an antihistamine that works by blocking a natural substance called histamine in your body. It reduces allergic reactions, helps you sleep, and can calm coughing by acting on the brain's cough and sleep centers.
What is it used for?
Allergies (sneezingitchingwatery eyesrunny nose)sleeplessnesscoughmotion sickness (travel sickness)itchy skin rashescold symptoms
Available Over The Counter
Available at pharmacies without a prescription. Rules may vary by country.
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