Drug interactions
Dextroamphetamine + Marijuana
Severity: Moderate
Dextroamphetamine and Marijuana: 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
Cannabis can cause tachycardia, anxiety and impaired cognition, and dextroamphetamine also increases heart rate and may worsen anxiety or psychosis-like symptoms. Their sedative and stimulant effects may partly mask each other, which can lead to misjudged impairment.
What this interaction means in plain words
Dextroamphetamine and Marijuana 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 sympathomimetic cardiovascular effects and opposing CNS effects; no specific pharmacokinetic mechanism is established.
What to do
Counsel patients to avoid cannabis while on amphetamine therapy. Monitor heart rate, blood pressure and psychiatric symptoms if use continues.
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 Marijuana?
MediHelp rates the interaction as moderate. Dextroamphetamine and Marijuana 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. Cannabis can cause tachycardia, anxiety and impaired cognition, and dextroamphetamine also increases heart rate and may worsen anxiety or psychosis-like symptoms. Their sedative and stimulant effects may partly mask each other, which can lead to misjudged impairment.
How serious is the interaction between Dextroamphetamine and Marijuana?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Counsel patients to avoid cannabis while on amphetamine therapy. Monitor heart rate, blood pressure and psychiatric symptoms if use continues.
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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