Drug interactions
Diazepam + Pentobarbital
Severity: Major
Diazepam and Pentobarbital: major interaction.
Last updated Sources: US FDA label
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
Pentobarbital adds to diazepam's CNS and respiratory depression, raising the risk of deep sedation and apnea. Barbiturates also induce hepatic enzymes and can lower diazepam levels over time.
What this interaction means in plain words
Diazepam and Pentobarbital 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
Additive GABA-A mediated CNS depression plus CYP3A4 induction by pentobarbital increasing diazepam clearance.
What to do
Avoid routine combination; if both are needed, monitor sedation, respiration and oxygenation closely and reduce doses. Reassess diazepam dose with prolonged barbiturate use.
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?
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References
Other interactions of Diazepam
Frequently asked questions
Can I take Diazepam with Pentobarbital?
MediHelp rates the interaction as major. Diazepam and Pentobarbital 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. Pentobarbital adds to diazepam's CNS and respiratory depression, raising the risk of deep sedation and apnea. Barbiturates also induce hepatic enzymes and can lower diazepam levels over time.
How serious is the interaction between Diazepam and Pentobarbital?
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 routine combination; if both are needed, monitor sedation, respiration and oxygenation closely and reduce doses. Reassess diazepam dose with prolonged barbiturate use.
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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