Drug interactions
Phenylephrine + Protriptyline
Severity: Moderate
Phenylephrine and Protriptyline: moderate 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
Protriptyline strongly blocks norepinephrine reuptake and can amplify the pressor response to phenylephrine. This may cause hypertension and arrhythmias.
What this interaction means in plain words
Phenylephrine and Protriptyline can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Why it happens
Norepinephrine reuptake inhibition by protriptyline potentiates adrenergic receptor stimulation.
What to do
Monitor blood pressure and heart rate, and use a reduced starting dose of systemic phenylephrine; avoid oral decongestants when possible.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Phenylephrine
- Isocarboxazid + Phenylephrine Contraindicated
- Phenelzine + Phenylephrine Contraindicated
- Phenylephrine + Tranylcypromine Contraindicated
- Bromocriptine + Phenylephrine Major
- Cocaine + Phenylephrine Major
- Dihydroergotamine intranasal + Phenylephrine Major
Frequently asked questions
Can I take Phenylephrine with Protriptyline?
MediHelp rates the interaction as moderate. Phenylephrine and Protriptyline can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Protriptyline strongly blocks norepinephrine reuptake and can amplify the pressor response to phenylephrine. This may cause hypertension and arrhythmias.
How serious is the interaction between Phenylephrine and Protriptyline?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor blood pressure and heart rate, and use a reduced starting dose of systemic phenylephrine; avoid oral decongestants when possible.
What other medicines interact with Phenylephrine?
MediHelp also lists interactions of Phenylephrine with, for example, Isocarboxazid, Phenelzine, Tranylcypromine. The full list is on the Phenylephrine page.
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