How does diphenhydramine treat allergies and the common cold?

Stacy Wiegman, PharmD

Pharmacy

Diphenhydramine works by blocking the effects of the histamine naturally found in many cells of the body. This medication relieves only the symptoms of allergies and the common cold, but will not treat the underlying causes. Symptoms that may be relieved by diphenhydramine include: watery eyes, itching, rash, hives, coughing, runny nose and sneezing.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.