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Diphenhydramine IV
Diphenhydramine is a first-generation antihistamine that blocks H1 histamine receptors to reduce allergic and inflammatory responses.
Diphenhydramine is a first-generation antihistamine that blocks H1 histamine receptors to reduce allergic and inflammatory responses. Used for Acute allergic reactions, Anaphylaxis (adjunctive therapy), Urticaria and pruritus.
At a glance
| Generic name | Diphenhydramine IV |
|---|---|
| Sponsor | Hoffmann-La Roche |
| Drug class | First-generation H1 receptor antagonist (antihistamine) |
| Target | H1 histamine receptor |
| Modality | Small molecule |
| Therapeutic area | Allergy/Immunology |
| Phase | Phase 3 |
Mechanism of action
Diphenhydramine competitively antagonizes H1 histamine receptors on various tissues, preventing histamine-mediated effects such as itching, urticaria, and allergic reactions. The IV formulation provides rapid onset of action for acute allergic reactions and anaphylaxis. It also has anticholinergic and sedating properties due to central nervous system penetration.
Approved indications
- Acute allergic reactions
- Anaphylaxis (adjunctive therapy)
- Urticaria and pruritus
- Allergic rhinitis
Common side effects
- Drowsiness/sedation
- Anticholinergic effects (dry mouth, urinary retention)
- Dizziness
- Headache
- Paradoxical excitation (especially in children)
Key clinical trials
- Sacituzumab Tirumotecan (MK-2870) in Combination With Pembrolizumab Versus Pembrolizumab Alone in Metastatic Non-small Cell Lung Cancer (NSCLC) With Programmed Cell Death Ligand 1 (PD-L1) Tumor Proportion Score (TPS) ≥ 50% (MK-2870-007) (PHASE3)
- A Study of Daratumumab, Carfilzomib, Lenalidomide, and Dexamethasone in Patients With Newly-Diagnosed Multiple Myeloma (PHASE2)
- A Clinical Study of Gocatamig (MK-6070) and Infinatamab Deruxtecan (MK-2400) in People With Small Cell Lung Cancer (MK-6070-003) (PHASE1, PHASE2)
- Cetuximab After Immunotherapy for the Treatment of Head and Neck Squamous Cell Cancer (PHASE2)
- Durvalumab and Vicineum in Subjects With High-Grade Non-Muscle-Invasive Bladder Cancer Previously Treated With Bacillus Calmette-Guerin (BCG) (PHASE1)
- Tazemetostat and Palbociclib With CPX-351for R/R AML (PHASE1)
- Losartan, Pembrolizumab and Stereotactic Body Radiation Therapy for the Treatment of Patients With Locally Recurrent, Refractory or Oligometastatic Head and Neck Squamous Cell Carcinoma (PHASE1)
- A Phase II Study of Axicabtagene Ciloleucel, an Anti-CD19 Chimeric Antigen Receptor (CAR) Tcell Therapy, in Combination With Radiotherapy (RT) in Relapsed/Refractory Follicular Lymphoma (PHASE2)
Primary sources
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| Source | Used for |
|---|---|
| ClinicalTrials.gov | Trial enrolment, design, endpoints, results |