What the FDA labels say about taking them together
Opicapone and phenelzine
Opicapone's FDA label of October 15, 2025 names phenelzine in its drug interactions section; the phenelzine label PlainMeds reads does not name opicapone. The opicapone label: “DRUG INTERACTIONS 7.1 Non-Selective Monoamine Oxidase (MAO) Inhibitors Both ONGENTYS and non-selective MAO inhibitors inhibit catecholamine metabolism, leading to increased levels of catecholamines.”
Check it at the source: the opicapone FDA label on DailyMed (effective October 15, 2025, Amneal Pharmaceuticals LLC); the phenelzine FDA label on DailyMed (effective June 6, 2025, Parke-Davis Div of Pfizer Inc).
What does the opicapone label say about phenelzine?
Opicapone label, drug interactionsDRUG INTERACTIONS 7.1 Non-Selective Monoamine Oxidase (MAO) Inhibitors Both ONGENTYS and non-selective MAO inhibitors (e.g., phenelzine, isocarboxazid, and tranylcypromine) inhibit catecholamine metabolism, leading to increased levels of catecholamines.
Source: FDA drug label (ONGENTYS), Amneal Pharmaceuticals LLC, effective October 15, 2025 (SPL set a511a531-112e-43f8-a43f-5334b0efe979), via openFDA; the full label on DailyMed
What does the phenelzine label say about opicapone?
Phenelzine's label (effective June 6, 2025) does not name opicapone in these sections. A label lists what its studies and reports found; it is not a complete list.
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
| Opicapone | Phenelzine | |
|---|---|---|
| Labeled for | Parkinson's disease | n/a |
| Boxed warning | No | Yes |
| Pharmacy cost (NADAC) | $24.67 per capsule 25 mg capsule | $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