Drug interactions
Ketoconazole + Marijuana
Severity: Moderate
Ketoconazole 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
Ketoconazole can raise systemic concentrations of cannabinoids such as THC and cannabidiol. This may intensify sedation, dizziness, tachycardia and impaired cognition.
What this interaction means in plain words
Ketoconazole 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
Ketoconazole inhibits CYP3A4, which contributes to cannabinoid metabolism.
What to do
Advise patients to use lower cannabis doses and avoid driving or hazardous tasks; monitor for excessive sedation and tachycardia.
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 Ketoconazole
- Alfuzosin + Ketoconazole Contraindicated
- Alprazolam + Ketoconazole Contraindicated
- Avanafil + Ketoconazole Contraindicated
- Conivaptan + Ketoconazole Contraindicated
- Dihydroergotamine intranasal + Ketoconazole Contraindicated
- Dihydroergotamine + Ketoconazole Contraindicated
Frequently asked questions
Can I take Ketoconazole with Marijuana?
MediHelp rates the interaction as moderate. Ketoconazole 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. Ketoconazole can raise systemic concentrations of cannabinoids such as THC and cannabidiol. This may intensify sedation, dizziness, tachycardia and impaired cognition.
How serious is the interaction between Ketoconazole 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: Advise patients to use lower cannabis doses and avoid driving or hazardous tasks; monitor for excessive sedation and tachycardia.
What other medicines interact with Ketoconazole?
MediHelp also lists interactions of Ketoconazole with, for example, Alfuzosin, Alprazolam, Avanafil. The full list is on the Ketoconazole page.
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