Benadryl^®

Generic Drug
Diphenhydramine Hydrochloride

 Dosage Forms

Syrup, 12.5 mg per 5 ml
Other forms of diphenhydramine are available, but only the syrup form is approved as an antitussive

 
Adult Dosing Guidelines

• For the control of coughing: 25 mg (10 ml) every 4 hours, not to exceed 100mg (40ml) in 24 hours

 
Pediatric Dosing Guidelines

• Is patient taking any other antihistamines or other products for cough?
• Is patient allergic to any antihistamines?
• Does patient have narrow angle glaucoma, peptic ulcer, urinary retention, high blood pressure, lower respiratory tract symptoms (such as asthma) or taking a monoamine oxidase inhibitor (MAOi)?
• Is patient pregnant or nursing?
• Is patient less than 2 years old?

Do not recommend diphenhydramine if patient answers yes to any of these questions.

Diphenhydramine is a reversible, competitive H1 receptor antagonist in both the peripheral and in the central nervous system. Antihistamines will prevent, but not reverse, histamine-mediated reactions. Therapeutic effects begin to occur 15-30 minutes after administration and last for 4-6 hours. Peak effects are seen 1-2 hours after administration. Diphenhydramine is a category B drug. Its use is contraindicated during the third trimester of pregnancy.


Adverse Reactions/Side Effects
Drowsiness (most common), photosensitivity, dizziness, dry mouth, GI upset


Natural Products or Nutritional Interactions
Avoid alcohol while taking this medication.