What class of drug is diphenhydramine (Benadryl)?

Diphenhydramine, commonly known by the brand name Benadryl, belongs to the class of drugs known as antihistamines. Antihistamines work primarily by blocking the action of histamine, a substance in the body that is responsible for allergic symptoms such as itching, sneezing, runny nose, and hives. They are commonly used to treat allergic reactions, the common cold, and motion sickness, among other conditions.

Antihistamines like diphenhydramine are effective in alleviating symptoms associated with allergies, making their classification as antihistamines accurate and appropriate. This classification reflects their mechanism of action and therapeutic use. Other options, such as decongestants, cough suppressants, and pain relievers, have different mechanisms of action and are used for different indications, which underscores why diphenhydramine is specifically categorized as an antihistamine.