Wait
Initial observation time of 48 hours, as noted in the allergy sheet's table, or 5 times the half-life or maximal dosing interval after the last dose
A general FAA rule gives a different wait. The specific one applies.
Examiner
The examiner can issue when the document's criteria are met
FAA label
CONDITIONALLY ACCEPTABLE
The FAA's allergy sheet lists oral cetirizine (Zyrtec) as conditionally acceptable; it may be used occasionally (1-2 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.
Track your medicationsCompare FAA documents: cetirizineWhat each of the two FAA documents says, in plain wordsOpen
The FAA's documents differ. The allergy sheet lists cetirizine and levocetirizine as conditionally acceptable with a 48-hour initial observation; the general over-the-counter guide lists both as No Go with a five-dosage-interval wait.
Its table gives an initial observation time of 48 hours; 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 allergy sheet also says airmen who are exhibiting symptoms, regardless of the treatment used, must not fly.
The FAA's over-the-counter guide lists cetirizine (Zyrtec) among its sedating products to avoid, as "No Go", and says to wait at least five dosage intervals after the last dose before flying if the pilot takes any of its No Go medications.
Show the FAA's words: cetirizineThe official FAA wording: four passages, each with its document and dateOpen
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: Some Second-Generation Histamine-H1 receptor antagonist
cetirizine (Zyrtec)
levocetirizine (Xyzal)
48 hours
48 hours
Airmen who are exhibiting symptoms, regardless of the treatment used, must not fly.
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.
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.
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.