Drug interactions
Phenylephrine po + Tranylcypromine
Severity: Contraindicated
Phenylephrine po and Tranylcypromine: 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
Oral phenylephrine has its gut and liver first-pass metabolism by MAO reduced during MAO inhibition, so its systemic exposure and pressor effect can rise substantially. Hypertensive crisis is possible.
What this interaction means in plain words
Phenylephrine po and Tranylcypromine 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.
Why it happens
MAO inhibition blocks first-pass metabolism of phenylephrine and potentiates adrenergic stimulation.
What to do
Avoid oral phenylephrine, including in OTC cold products, during and for 14 days after tranylcypromine. Advise patients to check decongestant ingredients.
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 Tranylcypromine
- 5-HTP + Tranylcypromine Contraindicated
- Amitriptyline + Tranylcypromine Contraindicated
- Amoxapine + Tranylcypromine Contraindicated
- Atomoxetine + Tranylcypromine Contraindicated
- Benzphetamine + Tranylcypromine Contraindicated
- Brimonidine + Tranylcypromine Contraindicated
Frequently asked questions
Can I take Phenylephrine po with Tranylcypromine?
MediHelp rates the interaction as contraindicated. Phenylephrine po and Tranylcypromine 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. Oral phenylephrine has its gut and liver first-pass metabolism by MAO reduced during MAO inhibition, so its systemic exposure and pressor effect can rise substantially. Hypertensive crisis is possible.
How serious is the interaction between Phenylephrine po and Tranylcypromine?
MediHelp rates it contraindicated, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid oral phenylephrine, including in OTC cold products, during and for 14 days after tranylcypromine. Advise patients to check decongestant ingredients.
What other medicines interact with Tranylcypromine?
MediHelp also lists interactions of Tranylcypromine with, for example, 5-HTP, Amitriptyline, Amoxapine. The full list is on the Tranylcypromine page.
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