What the FDA labels say about taking them together
Amitriptyline and phenelzine
Phenelzine's FDA label of June 6, 2025 names amitriptyline in its warnings section; amitriptyline's label does not name phenelzine itself but warns about its class (MAO inhibitors).
Check it at the source: the amitriptyline FDA label on DailyMed (effective September 8, 2026, Sun Pharmaceutical Industries, Inc.); the phenelzine FDA label on DailyMed (effective June 6, 2025, Parke-Davis Div of Pfizer Inc).
What does the amitriptyline label say about phenelzine?
Amitriptyline's label does not name phenelzine itself; it warns about its class (MAO inhibitors):
Amitriptyline label, warningsSerotonin Syndrome The development of a potentially life-threatening serotonin syndrome has been reported with tricyclic antidepressants, including amitriptyline hydrochloride, alone but particularly with concomitant use of other serotonergic drugs (including triptans, tricyclic antidepressants, SSRI/SNRI, fentanyl, lithium, tramadol, tryptophan, buspirone, and St. …
Amitriptyline label, contraindicationsIt should not be given concomitantly with monoamine oxidase inhibitors.
Source: FDA drug label (Amitriptyline Hydrochloride), Sun Pharmaceutical Industries, Inc., effective September 8, 2026 (SPL set 4e520c63-1cf6-40f6-a51c-3f9b0e181342), via openFDA; the full label on DailyMed
What does the phenelzine label say about amitriptyline?
Phenelzine label, warningsA List of Dibenzazepine Derivative Drugs by Generic Name Follows: nortriptyline hydrochloride amitriptyline hydrochloride perphenazine and amitriptyline hydrochloride clomipramine hydrochloride desipramine hydrochloride imipramine hydrochloride doxepin carbamazepine cyclobenzaprine HCl amoxapine maprotiline HCl trimipramine maleate protriptyline HCl mirtazapine NARDIL should be used with caution in combination with antihypertensive drugs, including thiazide diuretics and β-blockers, since exaggerated hypotensive effects may result.
Source: FDA drug label (Nardil), Parke-Davis Div of Pfizer Inc, effective June 6, 2025 (SPL set 513a41d0-37d4-4355-8a6d-a2c643bce6fa), via openFDA; the full label on DailyMed
These are the labels' own sentences. PlainMeds does not grade interactions; a pharmacist or prescriber can say what they mean for one person's medicines.
Both medicines on the record
| Amitriptyline | Phenelzine | |
|---|---|---|
| Labeled for | Depression | n/a |
| Boxed warning | Yes | Yes |
| Pharmacy cost (NADAC) | $0.03 per tablet 10 mg tablet | $0.586 per tablet 15 mg tablet |
| Shortage now | No current entry | No current entry |
Source: FDA NDC Directory, CMS NADAC of October 7, 2026 and the FDA Drug Shortage Database (FDA files October 8, 2026)
What next?
- Check more medicines together
- up to five at once