Drug interactions
Codeine + Marijuana
Severity: Moderate
Codeine 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 has sedative and psychomotor-impairing effects that add to those of opioids. Combined use can increase drowsiness, dizziness and impaired judgment.
What this interaction means in plain words
Codeine 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 CNS depression through cannabinoid and opioid receptor pathways.
What to do
Counsel the patient about additive sedation and avoidance of driving or hazardous tasks. Reduce the opioid dose if excessive sedation occurs.
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 Codeine
- Alvimopan + Codeine Contraindicated
- Codeine + Isocarboxazid Contraindicated
- Codeine + Olanzapine / samidorphan Contraindicated
- Codeine + Phenelzine Contraindicated
- Codeine + Tranylcypromine Contraindicated
- Alfentanil + Codeine Major
Frequently asked questions
Can I take Codeine with Marijuana?
MediHelp rates the interaction as moderate. Codeine 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 has sedative and psychomotor-impairing effects that add to those of opioids. Combined use can increase drowsiness, dizziness and impaired judgment.
How serious is the interaction between Codeine 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 the patient about additive sedation and avoidance of driving or hazardous tasks. Reduce the opioid dose if excessive sedation occurs.
What other medicines interact with Codeine?
MediHelp also lists interactions of Codeine with, for example, Alvimopan, Isocarboxazid, Olanzapine / samidorphan. The full list is on the Codeine page.
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