Diphenhydramine is an antihistamine that reduces the natural chemical histamine in the body.
Histamine can produce symptoms of sneezing, itching, watery eyes, and runny nose.
Pseudoephedrine is a decongestant that shrinks blood vessels in the nasal passages. Dilated
blood vessels can cause nasal congestion (stuffy nose).
The combination of diphenhydramine and pseudoephedrine is used to treat sneezing, cough,
runny or stuffy nose, itchy or watery eyes, hives, skin rash, itching, and other symptoms of allergies and
the common cold.
Diphenhydramine and pseudoephedrine may also be used for other purposes not listed in this
medication guide.