What the FDA labels say about taking them together
Buspirone and phenelzine
Phenelzine's FDA label of June 6, 2025 names buspirone in its contraindications section; buspirone's label does not name phenelzine itself but warns about its class (MAO inhibitors).
Check it at the source: the buspirone FDA label on DailyMed (effective December 22, 2023, Unichem Pharmaceuticals (USA), Inc.); the phenelzine FDA label on DailyMed (effective June 6, 2025, Parke-Davis Div of Pfizer Inc).
What does the buspirone label say about phenelzine?
Buspirone's label does not name phenelzine itself; it warns about its class (MAO inhibitors):
Buspirone label, contraindicationsThe use of monoamine oxidase inhibitors (MAOIs) intended to treat depression with buspirone or within 14 days of stopping treatment with buspirone is contraindicated because of an increased risk of serotonin syndrome and/or elevated blood pressure.
Buspirone label, contraindicationsStarting buspirone in a patient who is being treated with reversible MAOIs such as linezolid or intravenous methylene blue is also contraindicated because of an increased risk of serotonin syndrome (see WARNINGS , DOSAGE AND ADMINISTRATION and DRUG INTERACTIONS ).
Source: FDA drug label (Buspirone Hydrochloride), Unichem Pharmaceuticals (USA), Inc., effective December 22, 2023 (SPL set a6bdf140-075e-445e-a62d-633a4b97f3a8), via openFDA; the full label on DailyMed
What does the phenelzine label say about buspirone?
Phenelzine label, contraindicationsA List of MAO Inhibitors by Generic Name Follows: pargyline hydrochloride pargyline hydrochloride and methylclothiazide furazolidone isocarboxazid procarbazine tranylcypromine NARDIL should also not be used in combination with buspirone HCl, since several cases of elevated blood pressure have been reported in patients taking MAO inhibitors who were then given buspirone HCl.
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
| Buspirone | Phenelzine | |
|---|---|---|
| Labeled for | Anxiety | n/a |
| Boxed warning | No | Yes |
| Pharmacy cost (NADAC) | $0.043 per tablet 15 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