Drug interactions
Diazepam + Saquinavir
Severity: Major
Diazepam and Saquinavir: major interaction.
Last updated Sources: UK SmPC
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
Saquinavir, usually given with ritonavir, inhibits CYP3A4 and can increase diazepam concentrations. Increased and prolonged sedation and respiratory depression may result.
What this interaction means in plain words
Diazepam and Saquinavir 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.
Why it happens
Inhibition of CYP3A4 mediated diazepam metabolism, with further inhibition from the ritonavir booster.
What to do
Prefer a non-oxidatively metabolized benzodiazepine such as lorazepam. If diazepam is needed, reduce the dose and monitor for excessive sedation.
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?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Diazepam and Saquinavir, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 7 days on the web. No card needed.
References
Other interactions of Diazepam
Frequently asked questions
Can I take Diazepam with Saquinavir?
MediHelp rates the interaction as major. Diazepam and Saquinavir 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. Saquinavir, usually given with ritonavir, inhibits CYP3A4 and can increase diazepam concentrations. Increased and prolonged sedation and respiratory depression may result.
How serious is the interaction between Diazepam and Saquinavir?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Prefer a non-oxidatively metabolized benzodiazepine such as lorazepam. If diazepam is needed, reduce the dose and monitor for excessive sedation.
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.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
