Drug interactions
Codeine + Doxylamine
Severity: Moderate
Codeine and Doxylamine: 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
Doxylamine is a strongly sedating antihistamine and adds to the drowsiness and CNS depression caused by codeine. Impaired alertness and next-day sedation are particular concerns.
What this interaction means in plain words
Codeine and Doxylamine 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; Doxylamine belongs to Respiratory.
Why it happens
Additive CNS depression from opioid agonism and central H1 antagonism.
What to do
Monitor for oversedation and advise against driving or alcohol. Avoid in older or respiratory-compromised patients where possible.
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 Doxylamine
Frequently asked questions
Can I take Codeine with Doxylamine?
MediHelp rates the interaction as moderate. Codeine and Doxylamine 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. Doxylamine is a strongly sedating antihistamine and adds to the drowsiness and CNS depression caused by codeine. Impaired alertness and next-day sedation are particular concerns.
How serious is the interaction between Codeine and Doxylamine?
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 for oversedation and advise against driving or alcohol. Avoid in older or respiratory-compromised patients where possible.
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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