Drug interactions
Codeine + Pentazocine
Severity: Moderate
Codeine and Pentazocine: 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
Pentazocine is a mixed agonist-antagonist that can reduce codeine analgesia and trigger withdrawal in opioid-dependent patients. It may also add to sedation and respiratory depression.
What this interaction means in plain words
Codeine and Pentazocine 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; Pentazocine belongs to Musculoskeletal.
Why it happens
Pentazocine partially antagonizes mu-opioid receptors and competes with codeine, while also adding CNS depression.
What to do
Avoid combining in opioid-tolerant patients and use a single opioid strategy where possible. If both are given, monitor for withdrawal, inadequate pain control and sedation.
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 Pentazocine
- Calcium / magnesium / potassium / sodium oxybates + Pentazocine Contraindicated
- Olanzapine / samidorphan + Pentazocine Contraindicated
- Pentazocine + Phenelzine Contraindicated
- Pentazocine + Tranylcypromine Contraindicated
- Alfentanil + Pentazocine Major
- Alprazolam + Pentazocine Major
Frequently asked questions
Can I take Codeine with Pentazocine?
MediHelp rates the interaction as moderate. Codeine and Pentazocine 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. Pentazocine is a mixed agonist-antagonist that can reduce codeine analgesia and trigger withdrawal in opioid-dependent patients. It may also add to sedation and respiratory depression.
How serious is the interaction between Codeine and Pentazocine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid combining in opioid-tolerant patients and use a single opioid strategy where possible. If both are given, monitor for withdrawal, inadequate pain control and sedation.
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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