diphenhydramine, Benadryl (cont.)

Pharmacy Author:
Medical and Pharmacy Editor:

SIDE EFFECTS: Diphenhydramine commonly can cause:

Diphenhydramine also may cause

Diphenhydramine should be used with caution (if at all) in persons with narrow-angle glaucoma, prostatic hypertrophy (enlarged prostate gland), hyperthyroidism, cardiovascular disease, high blood pressure (hypertension), and asthma.


PRESCRIPTION: No. Yes (Injection)


  • Capsules: 25 and 50 mg. Tablets: 12.5, 25 and 50 mg.
  • Tablet (Chewable or dispersible)): 12.5 mg.
  • Strips: 12.5 and 25 mg.
  • Elixir, oral solution, liquid: 12.5 mg per teaspoon (5 mL).
  • Strip: 25 mg. Injection: 50 mg per ml.
Medically Reviewed by a Doctor on 3/27/2015

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