Drug interactions
Codeine + Perphenazine
Severity: Moderate
Codeine and Perphenazine: 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
Both drugs depress the CNS, so the combination can cause greater sedation, hypotension and respiratory depression than either alone. Perphenazine is also a CYP2D6 inhibitor and may lessen conversion of codeine to morphine, which can reduce analgesia.
What this interaction means in plain words
Codeine and Perphenazine 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; Perphenazine belongs to Central Nervous System.
Why it happens
Additive CNS depression, plus CYP2D6 inhibition by perphenazine reducing codeine activation.
What to do
Start with low opioid doses and monitor sedation, blood pressure and respiratory rate. If analgesia is inadequate, consider an opioid not dependent on CYP2D6.
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
Other interactions of Perphenazine
- Ibutilide + Perphenazine Contraindicated
- Perphenazine + Pimozide Contraindicated
- Perphenazine + Thioridazine Contraindicated
- Adagrasib + Perphenazine Major
- Alfentanil + Perphenazine Major
- Amiodarone + Perphenazine Major
Frequently asked questions
Can I take Codeine with Perphenazine?
MediHelp rates the interaction as moderate. Codeine and Perphenazine 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. Both drugs depress the CNS, so the combination can cause greater sedation, hypotension and respiratory depression than either alone. Perphenazine is also a CYP2D6 inhibitor and may lessen conversion of codeine to morphine, which can reduce analgesia.
How serious is the interaction between Codeine and Perphenazine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Start with low opioid doses and monitor sedation, blood pressure and respiratory rate. If analgesia is inadequate, consider an opioid not dependent on CYP2D6.
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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