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Allergy and cold

Chlorpheniramine

First-generation antihistamine (sedating)
Other names: ChlorTrimeton, Coricidin HBP Cough & Cold

FAA guidance

Do not fly while taking it.

Wait

5 days

after the last dose

Other FAA documents add more.

If used routinely

The examiner should defer

FAA label

DO NOT FLY

Source: FAA, DO NOT ISSUE – DO NOT FLY Medications and general No Fly wait times. FAA date 30 September 2026. Checked by Crosscheck 14 October 2026

Chlorpheniramine is on the FAA's Do Not Fly list, and if the pilot uses it routinely, the FAA's table says the examiner should defer.

Track your medications
Compare FAA documents: chlorpheniramineWhat each of the three FAA documents says, in plain wordsOpen

Wait

  • the FAA's over-the-counter guide gives the 5 days, in its wait after the last dose of a No Go medication
  • the allergy sheet's table does not say which of its times is chlorpheniramine's
  • the sheet's alternative is 5 times the half-life or maximal dosing interval after the last dose

The FAA's allergy sheet lists it, taken orally, as conditionally acceptable — it may be used occasionally (one or two times a week) if other certification criteria are met, with the stipulation that the pilot not exercise the privileges of the airman certificate while taking it, and daily use is not acceptable — and its table lists chlorpheniramine among the first-generation medicines, prints fewer times than names beside them, and does not say which time is whose; the sheet says an initial observation time is required to mitigate central nervous system risk, either as noted in the table or 5 times the half-life or maximal dosing interval after the last dose.

The FAA's over-the-counter guide gives a wait time of 5 days for chlorpheniramine and lists it as "No Go", among the sedating products to avoid, which it says can cause incapacitation. The guide says to wait at least five dosage intervals after the last dose before flying if the pilot takes any of its No Go medications or has previously had side effects from the medication. The guide notes that the wait times for sedating antihistamines are longer than noted in its Dosage Interval Wait Timetable, due to their longer half-life, and to consult the examiner. The guide also says Coricidin is allowed if it does not contain chlorpheniramine, and names Coricidin HBP cough & cold as containing chlorpheniramine. All three documents are quoted.

Show the FAA's words: chlorpheniramineThe official FAA wording: six passages, each with its document and dateOpen
FAA, DO NOT ISSUE – DO NOT FLY Medications and general No Fly wait times · FAA date 30 September 2026
DO NOT FLY (DNF) MEDICATIONS
The following medications have aeromedically concerning safety profiles. All medications listed below may cause sedation or drowsiness, impairing cognitive function and seriously degrading pilot performance.
ALLERGY MEDICATIONS (1st GENERATION)
Sedating Antihistamines:
Found in many over-the-counter (OTC) allergy and other types of medications, as a single agent or in any combination product.
Applies to nasal, ophthalmic, AND oral formulations.
diphenhydramine (Benadryl)
chlorpheniramine (Coricidin; ChlorTrimeton)
FAA, DO NOT ISSUE – DO NOT FLY Medications and general No Fly wait times · FAA date 30 September 2026
DO NOT FLY (DNF) MEDICATIONS
AMEs should caution pilots on use and provide additional No Fly wait times where applicable. If applicant is using the following medications routinely, AMEs should DEFER.
FAA, Allergy – Antihistamines & Immunotherapy Medication · FAA date 30 September 2026
Conditionally acceptable medications:
May be used occasionally (1-2 times a week) with the stipulation that the airman not exercise the privileges of airman certificate while taking the medication.
Daily use is NOT acceptable.
Initial observation time: Required to mitigate central nervous system risk, either as noted in the table below or 5x the half-life or maximal dosing interval after the last dose.
FAA, Allergy – Antihistamines & Immunotherapy Medication · FAA date 30 September 2026
CONDITIONALLY ACCEPTABLE (Sedating) Antihistamine Medications
May be used occasionally (1-2 x per week) as a single agent or in any combination product if other certification criteria are met. NOT FOR DAILY USE.
Medication Drug Class Initial observation
Oral: All First-Generation Histamine-H1 receptor antagonist
diphenhydramine (Benadryl)**
doxylamine (Unisom)
brompheniramine
chlorpheniramine (Coricidin; ChlorTrimeton)
clemastine (No brand)
60 hours
60 hours
5 days
5 days
FAA, What Over-the-Counter (OTC) Medications Can I Take and Still Be Safe to Fly? · FAA date 28 August 2024
4. NO GO Medications:
If you take any of the NO GO medications listed in the OTC Medications Reference Table OR if you have previously had side effects from the medication, wait at least five (5) dosage intervals after the last dose before flying.
Caution: Sedating antihistamine medications have a long half-life so wait time is 60 hours for both diphenhydramine (Benadryl) and doxylamine (Unisom), 5 days for both chlorpheniramine and clemastine.
AVOID
These can cause incapacitation.
NO GO
Sedating products:
brompheniramine (Dimetapp)
cetirizine (Zyrtec)
chlorpheniramine (Chlor- Trimeton)
diphenhydramine (Benadryl)
levocetirizine Xyzal)
dimenhydrinate (Dramamine)
meclizine (Antivert)
Sedating antihistamines can cause drowsiness and impaired thinking and judgement.
NOTE: Sedating antihistamines are commonly found in autopsy after aircraft accidents. The wait times for these medications are longer than noted in the “Dosage Interval Wait Timetable” due to their longer half-life. Consult your AME.
FAA, What Over-the-Counter (OTC) Medications Can I Take and Still Be Safe to Fly? · FAA date 28 August 2024
Coricidin (allowed If it does not contain chlorpheniramine)
Coricidin HBP cough & cold (contains chlorpheniramine)
Sources and dates: chlorpheniramineThree FAA documents, with the FAA's date and when Crosscheck checked themOpen

See also

Medication guidance alone does not determine whether a pilot is medically qualified to fly. The underlying condition, dosage, side effects, medication combinations, and certification history may affect FAA eligibility.

For informational purposes only. Not legal or medical advice.