Drug interactions
Codeine + Diphenoxylate
Severity: Moderate
Codeine and Diphenoxylate: 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
Diphenoxylate is an opioid with CNS effects at higher doses and may add to the sedative and respiratory depressant effects of codeine. Combined constipating effects may also lead to ileus.
What this interaction means in plain words
Codeine and Diphenoxylate 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; Diphenoxylate belongs to Gastrointestinal Tract.
Why it happens
Additive opioid agonist effects on the CNS and gastrointestinal tract.
What to do
Avoid using both for diarrhea or pain unless needed; monitor sedation, respiratory rate and bowel function.
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 Diphenoxylate
Frequently asked questions
Can I take Codeine with Diphenoxylate?
MediHelp rates the interaction as moderate. Codeine and Diphenoxylate 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. Diphenoxylate is an opioid with CNS effects at higher doses and may add to the sedative and respiratory depressant effects of codeine. Combined constipating effects may also lead to ileus.
How serious is the interaction between Codeine and Diphenoxylate?
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 using both for diarrhea or pain unless needed; monitor sedation, respiratory rate and bowel function.
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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