Diphenhydramine
Brand names: Benadryl|Last verified: 2026-09-12
FAA Pathway: Do Not Fly — occasional use only (1–2 times a week), 60-hour no-fly after each dose
The FAA classifies diphenhydramine (Benadryl) as a sedating first-generation antihistamine. It is conditionally acceptable only for occasional use (1–2 times a week), never daily, and you must not fly for 60 hours after each dose. It is found in many OTC allergy, cold, and sleep products, including most "PM" formulas, and the FAA notes it is the medication most commonly found on autopsy after aircraft accidents.
Related Resources
Pilot Tip
Always report all medications on your FAA medical application (Form 8500-8, Item 17a), even OTC medications. Failure to disclose is a far bigger issue than the medication itself.
Certification Details
Sources
- FAA OTC Medication Guide
- FAA Do-Not-Issue/Do-Not-Fly Table (faa.gov/ame_guide/media/DNI_DNF_tables.pdf)
- FAA Pilot OTC Medications Reference Guide (faa.gov/pilots/medical_certification/media/OTCMedicationsforPilots.pdf)
- FAA OTC Medications Reference (faa.gov/ame_guide/media/AME_OTC_medications.pdf)
- FAA AME Guide — Pharmaceuticals: Allergy – Antihistamine & Immunotherapy (faa.gov/ame_guide/media/AllergyAntihistamineImmunotherapyMedication.pdf)
Last verified: 2026-09-12
Frequently Asked Questions
Is Diphenhydramine allowed for pilots?
The FAA considers Diphenhydramine (Benadryl) to be "Conditionally Approved" for medical certification purposes. The FAA classifies diphenhydramine (Benadryl) as a sedating first-generation antihistamine. It is conditionally acceptable only for occasional use (1–2 times a week), never daily, and you must not fly for 60 hours after each dose. It is found in many OTC allergy, cold, and sleep products, including most "PM" formulas, and the FAA notes it is the medication most commonly found on autopsy after aircraft accidents.
What is the FAA status of Diphenhydramine?
Diphenhydramine has a status of "Conditionally Approved" under FAA medical certification policy. The certification pathway is: Do Not Fly — occasional use only (1–2 times a week), 60-hour no-fly after each dose.
Can I fly while taking Diphenhydramine?
Flying while taking Diphenhydramine may be possible through the FAA's Special Issuance process. You will need to meet specific requirements and obtain approval before exercising pilot privileges. Consult an experienced AME for guidance.
Important Notice
The FAA does not publish a comprehensive list of “approved” medications. The information on this page represents our interpretation of publicly available FAA guidance and is provided for informational and educational purposes only. It does not constitute medical advice, legal advice, or a guarantee of certification outcome.
The primary issue with the FAA is always whether the underlying medical condition — not just the medication — is compatible with safe flight. You should only start, stop, or change medications after consulting your treating physician. Always consult with a qualified Aviation Medical Examiner (AME) for guidance specific to your situation. FAA policies are subject to change. ClearedMed is not affiliated with or endorsed by the FAA.