I suspect that will depend on why you were prescribed Amitriptyline in the first place and of course, the dosage you were prescribed will tend to corroborate or confirm the reason for the prescription.
On the assumption that the medication was not prescribed for depression, I would suggest that you obtain as much evidence as possible to that effect, in the way of a letter from your medical practitioner. If you are invited in aviation then I would suggest that you do this anyway and just file the letter away in case you ever have to tick the right box/wrong box on a medical questionnaire.