Pilots and Over the Counter Medicines


By Richard R. Grayson. M.D.

Senior Aviation Medial Examiner

Geneva, Illinois


            I remember when Benadryl (Diphenhydramine) was invented.  It was 1945. That’s the year I entered the University of Illinois medical school.

            It was the world’s first antihistamine, and as a young student I regarded it as a miracle. Just think: you could design synthetic medicines instead of looking for them in herbs and tree bark and molds.  So naturally, when my father had trouble with his hay fever one Sunday afternoon and was sneezing continually, I gave him a 50 milligram capsule of Benadryl.  Father normally repaired the house on Sunday afternoons.  This particular Sunday, he slept all afternoon.  That was the first time I had experience with the side effects of drugs.  That also was the last time Father took anything for his hay fever.

            Benadryl is a forbidden substance for pilots for good reason, but the trouble is, it is available over the counter and a lot of people take it.  It not only sedates you, but it also dries your mouth and may affect your vision and urination.  Look it up online under side effects.  Here’s a quote from Pilot Medical Solutions, Inc.®   Some medications or medical conditions that present no problem on the runway may have significant adverse effects at 10,000 feet. A good example is Benadryl, an over-the-counter cold medication, which is the most common drug found in the bodies of dead pilots.

            Chlortrimeton (chlorpheniramine maleate) was the next antihistamine developed.  It does the same thing to your brain as Benadryl and is hidden in a lot of so-called cold medicines. 

            I don’t see any reason to take anything that contains either of these drugs since we now have non-sedating antihistamines like Claritin that are okay with the FAA.  The following quote is from the FAA safety brochure for pilots:  You should read it and memorize it.

If you must take over-the-counter medications,


·     Read and follow the label directions.

·     If the label warns of significant side effects, do not fly after taking the medication until at least two dosing intervals have passed. For example, if the directions say to take the medication every 6 hours, wait until at least 12 hours after the last dose to fly.

·     Remember that you should not fly if the underlying condition that you are treating would make you unsafe if the medication fails to work.

·     Never fly after taking a new medication for the first time.

·     As with alcohol, medications may impair your ability to fly—even though you feel fine.

·     If you have questions about a medication, ask your aviation medical examiner.

·     When in doubt, don’t fly.”