Drug interactions
Dextroamphetamine + St john's wort
Severity: Moderate
Dextroamphetamine and St john's wort: 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
St John's wort has serotonergic activity and amphetamines increase serotonin release, so combined use may precipitate serotonin syndrome. Additive stimulant effects on blood pressure and heart rate may also occur.
What this interaction means in plain words
Dextroamphetamine and St john's wort 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 serotonergic and monoaminergic effects.
What to do
Advise patients to avoid St John's wort while taking dextroamphetamine. Monitor for signs of serotonin toxicity if the combination has been used.
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 St john's wort?
MediHelp rates the interaction as moderate. Dextroamphetamine and St john's wort 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. St John's wort has serotonergic activity and amphetamines increase serotonin release, so combined use may precipitate serotonin syndrome. Additive stimulant effects on blood pressure and heart rate may also occur.
How serious is the interaction between Dextroamphetamine and St john's wort?
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 St John's wort while taking dextroamphetamine. Monitor for signs of serotonin toxicity if the combination has been used.
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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