Drug interactions
Methamphetamine + Phenylephrine po
Severity: Moderate
Methamphetamine and Phenylephrine po: 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
Oral phenylephrine is a vasoconstrictor decongestant, and combining it with methamphetamine adds to the pressor and stimulant effects. Patients may develop higher blood pressure, palpitations, tachycardia and agitation.
What this interaction means in plain words
Methamphetamine and Phenylephrine po 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
Additive adrenergic stimulation: direct alpha-1 agonism from phenylephrine plus indirect catecholamine release from methamphetamine.
What to do
Avoid decongestants in patients taking methamphetamine, especially those with hypertension or heart disease. Monitor blood pressure and heart rate if use is necessary.
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?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Methamphetamine and Phenylephrine po, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 7 days on the web. No card needed.
Other interactions of Methamphetamine
- Isocarboxazid + Methamphetamine Contraindicated
- Linezolid + Methamphetamine Contraindicated
- Methamphetamine + Phenelzine Contraindicated
- Methamphetamine + Procarbazine Contraindicated
- Methamphetamine + Rasagiline Contraindicated
- Methamphetamine + Safinamide Contraindicated
Frequently asked questions
Can I take Methamphetamine with Phenylephrine po?
MediHelp rates the interaction as moderate. Methamphetamine and Phenylephrine po 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. Oral phenylephrine is a vasoconstrictor decongestant, and combining it with methamphetamine adds to the pressor and stimulant effects. Patients may develop higher blood pressure, palpitations, tachycardia and agitation.
How serious is the interaction between Methamphetamine and Phenylephrine po?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid decongestants in patients taking methamphetamine, especially those with hypertension or heart disease. Monitor blood pressure and heart rate if use is necessary.
What other medicines interact with Methamphetamine?
MediHelp also lists interactions of Methamphetamine with, for example, Isocarboxazid, Linezolid, Phenelzine. The full list is on the Methamphetamine page.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
