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Benadryl Allergy Side Effects

Generic name: diphenhydramine

Medically reviewed by Drugs.com. Last updated on Oct 3, 2024.

Note: This document provides detailed information about Benadryl Allergy.

Applies to diphenhydramine: oral capsules and tablets, parenteral injection Side Effects associated with diphenhydramine. Some dosage forms listed on this page may not apply specifically to the brand name Benadryl Allergy.

Applies to diphenhydramine: oral capsules and tablets, parenteral injection.

Side effects include:

Sedation, sleepiness, dizziness, disturbed coordination, epigastric distress, thickening of bronchial secretions.

For healthcare professionals

Applies to diphenhydramine: compounding powder, injectable solution, oral capsule, oral disintegrating strip, oral liquid, oral tablet, oral tablet chewable, oral tablet disintegrating.

General adverse events

The most commonly reported side effects included somnolence, dizziness, and incoordination.[Ref]

Nervous system

Drowsiness usually diminishes after a few days.[Ref]

Gastrointestinal

Other

Psychiatric

Cardiovascular

Hematologic

Hypersensitivity

Hepatic

Dermatologic

Respiratory

Genitourinary

Ocular

Metabolic

Musculoskeletal

References

1. (2002) "Product Information. Benadryl (diphenhydramine)." Parke-Davis

2. (2022) "Product Information. Benadryl Children's Allergy Fastmelt (diphenhydrAMINE)." Pfizer U.S. Pharmaceuticals Group

3. Cerner Multum, Inc. "UK Summary of Product Characteristics."

4. Cerner Multum, Inc. "Australian Product Information."

Frequently asked questions

Further information

Benadryl Allergy side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.