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Diphenhydramine hydrochloride is a first-generation antihistamine found in numerous over-the-counter products. A common single-ingredient tablet contains 25 mg. It temporarily relieves runny nose, sneezing, itchy or watery eyes, and itching of the nose or throat from hay fever or other upper respiratory allergies, plus runny nose and sneezing from the common cold.
read more about diphenhydramine ...Diphenhydramine blocks histamine H1 receptors and reduces histamine-related symptoms in the nose, eyes, throat, and other tissues. It also crosses into the central nervous system, which contributes to marked drowsiness. Anticholinergic activity contributes to dry mouth, blurred vision, and urinary difficulty in susceptible patients.
Current single-ingredient 25 mg OTC labeling covers temporary relief of sneezing, runny nose, itchy or watery eyes, and itching of the nose or throat from hay fever or other upper respiratory allergies. It also temporarily relieves runny nose and sneezing associated with the common cold.
Adults and children age 12 and older take one or two 25 mg tablets every four to six hours and should not exceed six doses in 24 hours. Children age 6 to under 12 take one tablet every four to six hours. Current tablet labeling states that children younger than 6 should not use the product.
Marked drowsiness can occur, and alcohol, sedatives, or tranquilizers can increase this effect. Medical advice is recommended before use in people with glaucoma, chronic bronchitis, emphysema, or difficulty urinating due to an enlarged prostate. Current OTC labeling states that diphenhydramine should not be used to make a child sleepy.
Yes. Diphenhydramine is a first-generation histamine H1 receptor antagonist.
Adults and children age 12 and older take one or two tablets every four to six hours, up to six doses daily.
Yes. Marked drowsiness can occur, and alcohol or other sedating medicines can intensify it.
No. Current OTC labeling states that it should not be used to make a child sleepy.
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