Drug interactions
Codeine + Phenelzine
Severity: Contraindicated
Codeine and Phenelzine: contraindicated 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
Phenelzine, a nonselective MAOI, taken with codeine can cause serotonin syndrome or an opioid-MAOI reaction with hypertension or hypotension, hyperthermia, agitation, coma and respiratory depression. The reaction can be severe.
What this interaction means in plain words
Codeine and Phenelzine are not normally used together. Taking them at the same time is expected to cause harm or make one of them unsafe, so a different medicine is usually chosen for one of the two.
Codeine belongs to Musculoskeletal; Phenelzine belongs to Central Nervous System.
Why it happens
Irreversible MAO inhibition combined with opioid serotonergic and CNS depressant effects produces serotonin toxicity and exaggerated opioid effects.
What to do
Do not use codeine during or within 14 days after stopping phenelzine. Choose a non-serotonergic analgesic instead.
What to ask your pharmacist
- Is there an alternative to one of these two medicines for me?
- If both are essential, who is monitoring me and how often?
- Which symptoms mean I should stop and seek help straight away?
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Other interactions of Codeine
- Alvimopan + Codeine Contraindicated
- Codeine + Isocarboxazid Contraindicated
- Codeine + Olanzapine / samidorphan Contraindicated
- Codeine + Tranylcypromine Contraindicated
- Alfentanil + Codeine Major
- Alprazolam + Codeine Major
Other interactions of Phenelzine
- 5-HTP + Phenelzine Contraindicated
- Amitriptyline + Phenelzine Contraindicated
- Amoxapine + Phenelzine Contraindicated
- Atomoxetine + Phenelzine Contraindicated
- Benzphetamine + Phenelzine Contraindicated
- Brimonidine + Phenelzine Contraindicated
Frequently asked questions
Can I take Codeine with Phenelzine?
MediHelp rates the interaction as contraindicated. Codeine and Phenelzine are not normally used together. Taking them at the same time is expected to cause harm or make one of them unsafe, so a different medicine is usually chosen for one of the two. Phenelzine, a nonselective MAOI, taken with codeine can cause serotonin syndrome or an opioid-MAOI reaction with hypertension or hypotension, hyperthermia, agitation, coma and respiratory depression. The reaction can be severe.
How serious is the interaction between Codeine and Phenelzine?
MediHelp rates it contraindicated, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Do not use codeine during or within 14 days after stopping phenelzine. Choose a non-serotonergic analgesic instead.
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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