Diphenhydramine

Generic name: diphenhydramine [ DYE-fen-HYE-dra-meen ]
Brand names: Allergy Relief, Allermax, Banophen, Benadryl, Compoz Nighttime Sleep Aid, ... show all 27 brands Diphedryl, Diphenhist, Dytuss, Nytol QuickCaps, PediaCare Children's Allergy, Q-Dryl, QlearQuil Nightitme Allergy Relief, Quenalin, Scot-Tussin Allergy Relief Formula, Siladryl Allergy, Silphen Cough, Simply Sleep, Sleepinal, Sominex, Tranquil, Twilite, Unisom Sleepgels Maximum Strength, Valu-Dryl, Vanamine PD, Z-Sleep, ZzzQuil, plus many others
Drug classes:Anticholinergic antiemetics, Anticholinergic antiparkinson agents, Antihistamines, Miscellaneous anxiolytics, sedatives and hypnotics

Medically reviewed by Sanjai Sinha, MD. Last updated on Dec 9, 2021.

What is diphenhydramine?

Diphenhydramine is an antihistamine that reduces the effects of natural chemical histamine in the body. Histamine can produce symptoms of sneezing, itching, watery eyes, and runny nose.

Diphenhydramine is used to treat sneezing, runny nose, watery eyes, hives, skin rash, itching, and other cold or allergy symptoms.

Diphenhydramine is also used to treat motion sickness, to induce sleep, and to treat certain symptoms of Parkinson's disease.

Diphenhydramine may also be used for purposes not listed in this medication guide.

Warnings

When taking diphenhydramine, use caution driving, operating machinery, or performing other hazardous activities. Diphenhydramine may cause dizziness or drowsiness. If you experience dizziness or drowsiness, avoid these activities.

Use alcohol cautiously. Alcohol may increase drowsiness and dizziness while takin