Drug interactions
Flurazepam + Ketoconazole
Severity: Moderate
Flurazepam and Ketoconazole: 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
Ketoconazole may reduce clearance of flurazepam's active metabolites, increasing and prolonging sedation, with risks of next-day impairment, falls and respiratory depression.
What this interaction means in plain words
Flurazepam and Ketoconazole 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
Ketoconazole inhibits CYP3A4, reducing flurazepam metabolism.
What to do
Use a lower flurazepam dose or an alternative hypnotic not dependent on CYP3A4, such as temazepam. Monitor for oversedation, especially in older adults.
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 Ketoconazole
- Alfuzosin + Ketoconazole Contraindicated
- Alprazolam + Ketoconazole Contraindicated
- Avanafil + Ketoconazole Contraindicated
- Conivaptan + Ketoconazole Contraindicated
- Dihydroergotamine intranasal + Ketoconazole Contraindicated
- Dihydroergotamine + Ketoconazole Contraindicated
Frequently asked questions
Can I take Flurazepam with Ketoconazole?
MediHelp rates the interaction as moderate. Flurazepam and Ketoconazole 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. Ketoconazole may reduce clearance of flurazepam's active metabolites, increasing and prolonging sedation, with risks of next-day impairment, falls and respiratory depression.
How serious is the interaction between Flurazepam and Ketoconazole?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Use a lower flurazepam dose or an alternative hypnotic not dependent on CYP3A4, such as temazepam. Monitor for oversedation, especially in older adults.
What other medicines interact with Ketoconazole?
MediHelp also lists interactions of Ketoconazole with, for example, Alfuzosin, Alprazolam, Avanafil. The full list is on the Ketoconazole page.
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