Drug interactions
Diazepam + Nefazodone
Severity: Moderate
Diazepam and Nefazodone: 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
Nefazodone inhibits CYP3A4 and can increase diazepam exposure, causing greater sedation and psychomotor impairment. The risk is greatest in older adults.
What this interaction means in plain words
Diazepam and Nefazodone 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
Nefazodone inhibits CYP3A4, decreasing diazepam metabolism, with additive sedation.
What to do
Monitor for excessive sedation and reduce the diazepam dose as needed. A benzodiazepine cleared by glucuronidation, such as lorazepam, may be preferred.
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 Diazepam
Frequently asked questions
Can I take Diazepam with Nefazodone?
MediHelp rates the interaction as moderate. Diazepam and Nefazodone 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. Nefazodone inhibits CYP3A4 and can increase diazepam exposure, causing greater sedation and psychomotor impairment. The risk is greatest in older adults.
How serious is the interaction between Diazepam and Nefazodone?
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 excessive sedation and reduce the diazepam dose as needed. A benzodiazepine cleared by glucuronidation, such as lorazepam, may be preferred.
What other medicines interact with Diazepam?
MediHelp also lists interactions of Diazepam with, for example, Calcium / magnesium / potassium / sodium oxybates, Alfentanil, Alprazolam. The full list is on the Diazepam page.
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