Diphenhydramine

Name: Diphenhydramine Drug Interactions
Creator: Dr. Brian Staiger, PharmD, BCPS

28 interactions 3 explained in plain English

Also sold as: Banophen Benadryl Calagel Reformulated Jun 2019 Compoz Dermamycin Diphedryl Diphenhist Dormin Genahist Kids-Eeze Allergy Nytol Pediaclear Cough Rest Simply Scot-Tussin Allergy Siladryl Simply Sleep Sleep-Eze Sleepinal Sominex Somnapure The Itch Eraser Twilite Unisom Sleep Vanamine Vetadryl Wal-Dryl Allergy Wal-Dryl Childrens Wal-Sleep Z Wal-Som Wal-Som Maximum Strength Z-Sleep ZZZ Sleep Zzzquil

Medically reviewed by Dr. Brian Staiger, PharmD, BCPS · Updated Jul 4, 2026 · Editorial policy · Data sources

Sources: FDA prescribing information (Structured Product Labeling), the published literature cited in each entry, DDInter 2.0 (a major open-access drug-interaction database), and legacy DrugBank interaction data distributed by the NIH's RxNav service (decommissioned in 2024) — analyzed and reviewed by our pharmacist team. How we build this library →

Most serious with: Hydromorphone Rectal Buprenorphine Nalbuphine Injection Morphine Injection Fentanyl Transdermal Patch Glucagon Injection / Solution

26 Major 2 Moderate

All (28) Major (26) Moderate (2)

Moderate

Diphenhydramine Amitriptyline Elavil Explained Increased anticholinergic effects (dry mouth, urinary retention) Details Diphenhydramine Clonidine Transdermal Patch Catapres An increased risk of sedation and somnolence Details

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Educational information only, not medical advice. Always confirm interactions with your pharmacist or prescriber before making any change to your medications.