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Drug

Diphenhydramine

Common brand names:

Benadryl

Pronounced

"dye-fen-HI-druh-meen"

Drug Interactions

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

Do not use with any other diphenhydramine product applied to the skin or taken by mouth because increased side effects may occur.

  • Negative Interactions

    1

    • Diphenhydramine

      Henbane

      Potential Negative Interaction

      Antihistamines, including diphenhydramine, can cause “anticholinergic” side effects such as dryness of mouth and heart palpitations. Henbane (Hyoscyamus niger) also has anticholinergic activity and side effects. Therefore, use with diphenhydramine could increase the risk of anticholinergic side effects, though apparently no interactions have yet been reported with diphenhydramine and henbane. Henbane should not be taken except by prescription from a physician trained in its use, as it is extremely toxic.

      Henbane
      Diphenhydramine
      ×
      1. Blumenthal M, ed. The Complete German Commission E Monographs. Austin, TX: American Botanical Council, 1998, 146.

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Drug information is selected from data included with permission and copyrighted by First DataBank, Inc. This is a summary and does not contain all possible information about this product. For complete information about this product or your specific health needs, ask your healthcare professional. Always seek the advice of your healthcare professional if you have any questions about this product or your medical condition. This information is not intended as individual medical advice and does not substitute for the knowledge and judgment of your healthcare professional. This information does not contain any assurances that this product is safe, effective or appropriate for you.

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