Drug interactions
Dextroamphetamine + Phenylephrine po
Severity: Moderate
Dextroamphetamine 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 an alpha-agonist decongestant that can raise blood pressure, an effect amplified by amphetamine. Together they may cause hypertension, palpitations and nervousness.
What this interaction means in plain words
Dextroamphetamine 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 effects: direct alpha-agonism plus amphetamine-induced catecholamine release.
What to do
Advise patients to avoid decongestants where possible and monitor blood pressure if used. Prefer non-sympathomimetic alternatives such as saline or intranasal steroids.
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 Dextroamphetamine
- Dextroamphetamine + Isocarboxazid Contraindicated
- Dextroamphetamine + Linezolid Contraindicated
- Dextroamphetamine + Methylene blue Contraindicated
- Dextroamphetamine + Phenelzine Contraindicated
- Dextroamphetamine + Rasagiline Contraindicated
- Dextroamphetamine + Safinamide Contraindicated
Frequently asked questions
Can I take Dextroamphetamine with Phenylephrine po?
MediHelp rates the interaction as moderate. Dextroamphetamine 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 an alpha-agonist decongestant that can raise blood pressure, an effect amplified by amphetamine. Together they may cause hypertension, palpitations and nervousness.
How serious is the interaction between Dextroamphetamine 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: Advise patients to avoid decongestants where possible and monitor blood pressure if used. Prefer non-sympathomimetic alternatives such as saline or intranasal steroids.
What other medicines interact with Dextroamphetamine?
MediHelp also lists interactions of Dextroamphetamine with, for example, Isocarboxazid, Linezolid, Methylene blue. The full list is on the Dextroamphetamine page.
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