Almost every pilot has stood in front of a bathroom cabinet the night before a flight, holding a packet of cold tablets and wondering: "Can I take this and still fly tomorrow?" Until now, the honest answer usually involved a phone call to an aviation medical examiner, a PDF table, or a forum thread of uneven quality.
This month the FAA added a new option. Its Office of Aerospace Medicine has published MedGuide, an online reference that lists medications considered acceptable for flying and the waiting periods that go with them. Here is what it contains, what it deliberately doesn't do yet, and how the same question is handled under EASA rules in Europe.
What MedGuide is
MedGuide sits inside the FAA's Guide for Aviation Medical Examiners. The FAA describes it as "a reference for airman medical certification and FAA Air Traffic Control Specialist (ATCS) clearance". The page is marked as version 1.0 and was last updated on 1 October 2026; AVweb reported the launch on 16 October.
For each medication, the tool can show three different waiting periods, which the FAA defines like this:
- Initial wait time (after the first dose): the observation period after starting a new medication, "to allow for therapeutic effect and ensure no adverse side effects occur".
- Subsequent dose wait time (after each dose): the time required after the last dose before reporting for flight duties.
- Discontinuation wait time (after the final dose): the time needed after stopping the medication to check there is no rebound of symptoms, no withdrawal risk, and that the condition is stable.
The general rule is spelled out clearly: "When starting a new medication, in most cases, a 48-hour wait time is required before returning to safety-related duties." Higher-risk medications may need longer, and medications with minimal systemic effects may need less, so the specific entry always takes priority.
In MedGuide, "pilot" covers all pilots, plus air traffic controllers who are not FAA employees, such as those at contract or military towers. FAA-employed controllers have their own reporting rules.
What it doesn't do (yet)
The first version only lists medications in the ALLOWED category, which the FAA defines as acceptable for flight "provided the condition is stable/aeromedically acceptable and no adverse side effects are present". The FAA says later versions will add conditional and unacceptable medications. In other words, if a drug is not in MedGuide today, that does not mean it is banned, and it certainly does not mean it is fine. It simply isn't covered yet.
The FAA is also careful to say that MedGuide "should not be used as the sole basis in making aeromedical determinations" and that it is not clinical advice. Two points in its rules matter most for everyday flying:
- The illness counts as much as the pill. "Wait times are not determined solely by the medication," the FAA writes; an extended observation period may be needed to confirm the underlying condition is stable.
- Side effects ground you. If any concerning side effect appears before a flight, you stop flying, as required by 14 CFR 61.53, and the FAA says pilots should notify their treating physician and/or the FAA before flying.
According to AVweb, the launch follows pressure from Congress: in September, a House committee advanced a bill that would require the FAA to publish comprehensive medication guidance, including prohibited drugs. That bill is separate from MedGuide.
The older FAA rules of thumb still apply
MedGuide doesn't replace the FAA's existing over-the-counter (OTC) medications guide for pilots, which is still linked from the FAA's medications page. That guide gives a simple rule for medications on its "NO GO" list, or any medication that has given you side effects before: wait at least five dosage intervals after the last dose before flying.
| Package instructions | Minimum wait before flying |
|---|---|
| Every 4 to 6 hours (use the higher number) | 30 hours |
| Every 8 hours, or three times a day | 40 hours |
| Every 12 hours, or twice a day | 60 hours |
Sedating antihistamines are the classic trap. The FAA guide notes that they "are commonly found in autopsy after aircraft accidents" and that their long half-life means longer waits: 60 hours for diphenhydramine (Benadryl) and doxylamine (Unisom), and 5 days for chlorpheniramine and clemastine. These ingredients often hide in night-time cold remedies and sleep aids, so read the active ingredients, not just the brand name. The same guide lists non-sedating fexofenadine and loratadine as generally safe to fly, and says plainly: "NEVER FLY AFTER TAKING A NEW MEDICATION FOR THE FIRST TIME UNTIL AT LEAST 48 HOURS HAVE PASSED AND NO SIDE EFFECTS ARE NOTED."
Behind all of this sit two short US regulations. 14 CFR 61.53 prohibits acting as pilot in command while taking medication that leaves you unable to meet your medical certificate's requirements (or, for operations without a medical, while you know of a condition that makes you unable to fly safely). 14 CFR 91.17 bans acting as a crewmember "while using any drug that affects the person's faculties in any way contrary to safety".
And in Europe? What EASA says
EASA has no searchable medication database like MedGuide. The rule is in Part-MED, point MED.A.020 "Decrease in medical fitness". It says licence holders, and student pilots flying solo, must not exercise their privileges when they "take or use any prescribed or non-prescribed medication which is likely to interfere with the safe exercise of the privileges" of their licence.
It goes one step further than the US rule: you must seek aero-medical advice "without undue delay and before exercising the privileges" of your licence when you "have commenced the regular use of any medication". Class 1 and Class 2 holders go to an AeMC or AME. LAPL holders can also go to the general medical practitioner who signed their medical certificate.
EASA's guidance material for MED.A.020 starts with three questions to ask before taking any medication and flying:
- Do I feel fit to fly?
- Do I really need to take medication at all?
- Have I given this particular medication a personal trial on the ground to ensure that it will not have any adverse effects on my ability to fly?
The same guidance then goes through common drug groups. A few examples: nasal corticosteroids are described as compatible with flying; NSAIDs and paracetamol "may be compatible" if the three questions are answered positively; cough medicines with codeine, dextromethorphan or pseudoephedrine are "not compatible with flying duties"; and for antihistamines, EASA notes that the condition itself may stop you flying and that expert advice should be sought, so that non-sedating antihistamines can be prescribed if treatment is needed. Like the FAA, EASA keeps coming back to the same idea: the condition you are treating can ground you even when the medicine doesn't.
A practical way to use all this
- Try new medicines on a non-flying day. Both authorities effectively ask for this; the FAA puts a number on it (48 hours in most cases).
- Ask whether you would be fit without the medicine. If the honest answer is no, the medication is masking a problem, and that problem goes flying with you.
- Read active ingredients. Combination cold and flu products are where sedating antihistamines, codeine and decongestants tend to hide.
- Plan for the wait. A 60-hour wait after a night-time cold tablet means that Thursday night's dose can still matter on Sunday morning.
- Beware the pressure to go. Booked aircraft, passengers waiting and a nice forecast are exactly when "I'm fine" becomes risky. That is plan continuation bias starting on the ground.
MedGuide is a useful step, especially for US pilots who until now had to piece together answers from several PDFs. It is only version 1.0, and it is careful to leave the final decision with the pilot and the AME. European pilots won't find an EASA equivalent, but the logic is the same on both sides of the Atlantic: test it on the ground, think about why you're taking it, and when in doubt, don't fly.
Cover: blister packs of tablets and capsules. Photo: Wikimedia Commons, CC0 (public domain dedication), cropped.
Sources
- FAA Office of Aerospace Medicine, MedGuide (version 1.0, last updated 1 October 2026)
- AVweb, "New FAA Tool Helps Pilots Check Medication Restrictions", 16 October 2026
- FAA, Pharmaceuticals (Therapeutics): Medication Guidelines for Pilots
- FAA, Over-the-Counter (OTC) Medications Reference Guide: What OTC Medications Can I Take and Still Be Safe to Fly? (PDF, updated 28 August 2024)
- 14 CFR 61.53, Prohibition on operations during medical deficiency
- 14 CFR 91.17, Alcohol or drugs
- EASA, Easy Access Rules for Medical Requirements (Part-MED): MED.A.020 and GM1 MED.A.020 (PDF)
