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Drug interactions

Chlordiazepoxide + Lonafarnib

Severity: Major

Chlordiazepoxide and Lonafarnib: major 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

Lonafarnib is a strong CYP3A inhibitor and may increase chlordiazepoxide exposure. This can lead to excess sedation and respiratory depression.

What this interaction means in plain words

Chlordiazepoxide and Lonafarnib can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.

Chlordiazepoxide belongs to Central Nervous System; Lonafarnib belongs to Miscellaneous.

Evidence level: Moderate

Why it happens

Lonafarnib inhibits CYP3A4, reducing chlordiazepoxide clearance.

What to do

Avoid if possible, or reduce the chlordiazepoxide dose and monitor for sedation. Consider lorazepam as an alternative.

What to ask your pharmacist

  • Does the benefit of taking both outweigh the risk in my case?
  • Do I need any blood test, ECG or other check while on both?
  • What early warning signs should I watch for, and what should I do if they appear?

Bring a full list of your medicines, including over-the-counter products, supplements and herbal remedies, to every pharmacy visit.

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Frequently asked questions

Can I take Chlordiazepoxide with Lonafarnib?

MediHelp rates the interaction as major. Chlordiazepoxide and Lonafarnib can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Lonafarnib is a strong CYP3A inhibitor and may increase chlordiazepoxide exposure. This can lead to excess sedation and respiratory depression.

How serious is the interaction between Chlordiazepoxide and Lonafarnib?

MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid if possible, or reduce the chlordiazepoxide dose and monitor for sedation. Consider lorazepam as an alternative.

What other medicines interact with Chlordiazepoxide?

MediHelp also lists interactions of Chlordiazepoxide with, for example, Alfentanil, Alprazolam, Amobarbital. The full list is on the Chlordiazepoxide page.

Full monographs, dosing and an interaction checker in the MediHelp app

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