Drug

Diphenhydramine

Common brand names:

Benadryl Allergy Kapseals, Benadryl Children's Allergy, Nytol, Compoz Nighttime Sleep Aid, Dytan, Miles Nervine, Sominex

Diphenhydramine is an antihistamine used to relieve allergic rhinitis (seasonal allergy) symptoms including sneezing, runny nose, itching, and watery eyes and to relieve itching and swelling associated with uncomplicated allergic skin reactions. It is also used as a short-term sleep aid, to control coughs due to colds or allergy, and to prevent/treat motion sickness. Diphenhydramine is available in nonprescription products alone and in combination with other nonprescription drugs, to treat symptoms of allergy, colds, and upper respiratory infections.

Summary of Interactions with Vitamins, Herbs, & Foods

  • 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.
The Drug-Nutrient Interactions table may not include every possible interaction. Taking medicines with meals, on an empty stomach, or with alcohol may influence their effects. For details, refer to the manufacturers’ package information as these are not covered in this table. If you take medications, always discuss the potential risks and benefits of adding a new supplement with your doctor or pharmacist.

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