Drug interactions
Duloxetine + Phenobarbital
Severity: Moderate
Duloxetine and Phenobarbital: 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
Phenobarbital is an enzyme inducer that may lower duloxetine exposure and weaken its effect. Both agents cause CNS depression, so sedation and dizziness may be additive.
What this interaction means in plain words
Duloxetine and Phenobarbital 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.
Why it happens
Phenobarbital induction of hepatic enzymes (including CYP1A2) increasing duloxetine clearance, plus additive CNS depression.
What to do
Monitor for reduced duloxetine response and sedation, and increase the dose if clinically needed. Review other CNS depressants.
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 Duloxetine
- Duloxetine + Isocarboxazid Contraindicated
- Duloxetine + Linezolid Contraindicated
- Duloxetine + Methylene blue Contraindicated
- Duloxetine + Phenelzine Contraindicated
- Duloxetine + Procarbazine Contraindicated
- Duloxetine + Rasagiline Contraindicated
Frequently asked questions
Can I take Duloxetine with Phenobarbital?
MediHelp rates the interaction as moderate. Duloxetine and Phenobarbital 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. Phenobarbital is an enzyme inducer that may lower duloxetine exposure and weaken its effect. Both agents cause CNS depression, so sedation and dizziness may be additive.
How serious is the interaction between Duloxetine and Phenobarbital?
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 reduced duloxetine response and sedation, and increase the dose if clinically needed. Review other CNS depressants.
What other medicines interact with Duloxetine?
MediHelp also lists interactions of Duloxetine with, for example, Isocarboxazid, Linezolid, Methylene blue. The full list is on the Duloxetine page.
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