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Benadryl (diphenhydramine)
Diphenhydramine (Benadryl) is a first-generation antihistamine first approved in 1946, now available OTC worldwide. It serves dual roles as an allergy medication and sleep aid due to its sedating properties. Off-patent and manufactured generically, it remains one of the most widely used OTC medications globally.
At a glance
| Generic name | diphenhydramine |
|---|---|
| Also known as | Benadryl, Nytol, Sominex, ZzzQuil |
| Sponsor | Johnson & Johnson (McNeil Consumer Healthcare) |
| Drug class | First-generation antihistamine, Sedative |
| Target | Histamine H4 receptor, Solute carrier family 22 member 2, 5-hydroxytryptamine receptor 2A |
| Modality | Small molecule |
| Therapeutic area | Neuroscience |
| Phase | FDA-approved |
| First approval | 1946-01-01 (United States) |
Approved indications
- Allergic conjunctivitis
- Insomnia
- Seasonal allergic rhinitis
- Vasomotor rhinitis
Common side effects
Key clinical trials
- Infusion of Cell Populations From Unlicensed Umbilical Cord Blood Units (NA)
- A Randomized, Double-Blind, Efficacy and Safety Study of AR 14 (AZILSARTAN MEDOXOMIL) Treatment and Withdrawal, Followed by an Open-Label Extension, in Children 6 to Less Than 18 Years of Age With Hyp (Phase 3)
- Replication of the ONTARGET Antihypertensive Trial in Healthcare Claims Data (N/A)
- Phase II Non-Randomized, Unblinded, Single-Center Trial of Telmisartan in Combination With Cytotoxic Regimens in Platinum-Resistant Ovarian Cancer Versus Historical Best Supportive Care (Phase 2)
- Metabolic Abnormalities, Telmisartan and HIV Infection (Phase 2)
- A Randomized, Open-label, Single-dose, Two-treatment, Two-sequence, Two-period, Crossover Bioequivalence Study of Test Losartan Potassium Tablets (Containing Losartan Potassium 100 mg) of Pharmtechnol (Phase 1)
- A Phase 1 Study of Venetoclax With Obinutuzumab and Magrolimab (VENOM) in Relapsed and Refractory Indolent B-cell Malignancies (Phase 1)
- A Phase 3 Randomized, Open-label, Multicenter Study of Isatuximab (SAR650984) in Combination With Lenalidomide and Dexamethasone Versus Lenalidomide and Dexamethasone in Patients With High-risk Smolde (Phase 3)
Primary sources
Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.
| Source | Used for |
|---|---|
| FDA label | Mechanism, indications, dosing, boxed warnings, drug interactions |
| ClinicalTrials.gov | Trial enrolment, design, endpoints, results |
Competitive intelligence
For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:
- Benadryl CI brief — competitive landscape report
- Benadryl updates RSS · CI watch RSS
- Johnson & Johnson (McNeil Consumer Healthcare) portfolio CI