Drug interactions
Codeine + Desvenlafaxine
Severity: Moderate
Codeine and Desvenlafaxine: 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
Desvenlafaxine is a weak to moderate CYP2D6 inhibitor at higher doses and may reduce activation of codeine to morphine, lessening analgesia. Both drugs also have serotonergic activity, so serotonin toxicity is possible.
What this interaction means in plain words
Codeine and Desvenlafaxine 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.
Codeine belongs to Musculoskeletal; Desvenlafaxine belongs to Central Nervous System.
Why it happens
CYP2D6 inhibition decreases conversion of codeine to morphine; additive serotonergic effects.
What to do
Monitor analgesic response and consider an opioid not dependent on CYP2D6 if control is poor. Watch for agitation, tremor and hyperthermia suggestive of serotonin toxicity.
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?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Codeine and Desvenlafaxine, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 7 days on the web. No card needed.
Other interactions of Codeine
- Alvimopan + Codeine Contraindicated
- Codeine + Isocarboxazid Contraindicated
- Codeine + Olanzapine / samidorphan Contraindicated
- Codeine + Phenelzine Contraindicated
- Codeine + Tranylcypromine Contraindicated
- Alfentanil + Codeine Major
Other interactions of Desvenlafaxine
- Desvenlafaxine + Isocarboxazid Contraindicated
- Desvenlafaxine + Methylene blue Contraindicated
- Desvenlafaxine + Phenelzine Contraindicated
- Desvenlafaxine + Rasagiline Contraindicated
- Desvenlafaxine + Safinamide Contraindicated
- Desvenlafaxine + Selegiline Contraindicated
Frequently asked questions
Can I take Codeine with Desvenlafaxine?
MediHelp rates the interaction as moderate. Codeine and Desvenlafaxine 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. Desvenlafaxine is a weak to moderate CYP2D6 inhibitor at higher doses and may reduce activation of codeine to morphine, lessening analgesia. Both drugs also have serotonergic activity, so serotonin toxicity is possible.
How serious is the interaction between Codeine and Desvenlafaxine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor analgesic response and consider an opioid not dependent on CYP2D6 if control is poor. Watch for agitation, tremor and hyperthermia suggestive of serotonin toxicity.
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.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
