Drug interactions
Phenelzine + Tolcapone
Severity: Contraindicated
Phenelzine and Tolcapone: contraindicated interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Tolcapone inhibits COMT, and nonselective MAO inhibition blocks the other major catecholamine degradation pathway. The combination may cause dangerous hypertension and tachycardia. Tolcapone labeling contraindicates nonselective MAOIs.
What this interaction means in plain words
Phenelzine and Tolcapone are not normally used together. Taking them at the same time is expected to cause harm or make one of them unsafe, so a different medicine is usually chosen for one of the two.
Phenelzine belongs to Central Nervous System; Tolcapone belongs to Central Nervous System.
Why it happens
Combined COMT and MAO inhibition prevents catecholamine metabolism.
What to do
Do not use together. Choose an alternative antidepressant in patients taking tolcapone.
What to ask your pharmacist
- Is there an alternative to one of these two medicines for me?
- If both are essential, who is monitoring me and how often?
- Which symptoms mean I should stop and seek help straight away?
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Other interactions of Phenelzine
- 5-HTP + Phenelzine Contraindicated
- Amitriptyline + Phenelzine Contraindicated
- Amoxapine + Phenelzine Contraindicated
- Atomoxetine + Phenelzine Contraindicated
- Benzphetamine + Phenelzine Contraindicated
- Brimonidine + Phenelzine Contraindicated
Other interactions of Tolcapone
- Isocarboxazid + Tolcapone Contraindicated
- Tolcapone + Tranylcypromine Contraindicated
- Metoclopramide + Tolcapone Major
- Apomorphine + Tolcapone Moderate
- Asenapine + Tolcapone Moderate
- Brexpiprazole + Tolcapone Moderate
Frequently asked questions
Can I take Phenelzine with Tolcapone?
MediHelp rates the interaction as contraindicated. Phenelzine and Tolcapone are not normally used together. Taking them at the same time is expected to cause harm or make one of them unsafe, so a different medicine is usually chosen for one of the two. Tolcapone inhibits COMT, and nonselective MAO inhibition blocks the other major catecholamine degradation pathway. The combination may cause dangerous hypertension and tachycardia. Tolcapone labeling contraindicates nonselective MAOIs.
How serious is the interaction between Phenelzine and Tolcapone?
MediHelp rates it contraindicated, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Do not use together. Choose an alternative antidepressant in patients taking tolcapone.
What other medicines interact with Phenelzine?
MediHelp also lists interactions of Phenelzine with, for example, 5-HTP, Amitriptyline, Amoxapine. The full list is on the Phenelzine page.
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