Drug interactions
Chloroquine + Phenobarbital
Severity: Moderate
Chloroquine 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 induces hepatic enzymes including CYP3A4 and may lower chloroquine concentrations. This could reduce chloroquine efficacy.
What this interaction means in plain words
Chloroquine 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
Enzyme induction by phenobarbital increases chloroquine metabolism.
What to do
Monitor clinical response and consider an alternative antimalarial if chloroquine efficacy is critical.
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 Chloroquine
- Chloroquine + Cisapride Contraindicated
- Chloroquine + Dofetilide Contraindicated
- Chloroquine + Dronedarone Contraindicated
- Chloroquine + Droperidol Contraindicated
- Chloroquine + Panobinostat Contraindicated
- Chloroquine + Pimozide Contraindicated
Frequently asked questions
Can I take Chloroquine with Phenobarbital?
MediHelp rates the interaction as moderate. Chloroquine 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 induces hepatic enzymes including CYP3A4 and may lower chloroquine concentrations. This could reduce chloroquine efficacy.
How serious is the interaction between Chloroquine 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 clinical response and consider an alternative antimalarial if chloroquine efficacy is critical.
What other medicines interact with Chloroquine?
MediHelp also lists interactions of Chloroquine with, for example, Cisapride, Dofetilide, Dronedarone. The full list is on the Chloroquine page.
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