Drug interactions
Sodium oxybate + Valproic acid
Severity: Major
Sodium oxybate and Valproic acid: 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
Valproate raises exposure to oxybate and increases the risk of excessive sedation, respiratory depression and coma. Both drugs depress the CNS. Labeling advises dose reduction of oxybate when valproate is added.
What this interaction means in plain words
Sodium oxybate and Valproic acid 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.
Sodium oxybate belongs to Central Nervous System; Valproic acid belongs to Central Nervous System.
Why it happens
Valproate may inhibit GHB dehydrogenase and related metabolism, raising oxybate levels, and the pharmacodynamic CNS depression is additive.
What to do
When valproate is started in a patient stabilised on sodium oxybate, reduce the nightly oxybate dose by at least 20%. Monitor for sedation and respiratory depression and titrate the dose to response.
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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Other interactions of Valproic acid
- Ertapenem + Valproic acid Contraindicated
- Imipenem / cilastatin / relebactam + Valproic acid Contraindicated
- Imipenem / cilastatin + Valproic acid Contraindicated
- Meropenem / vaborbactam + Valproic acid Contraindicated
- Meropenem + Valproic acid Contraindicated
- Calcium / magnesium / potassium / sodium oxybates + Valproic acid Major
Other interactions of Sodium oxybate
- Alprazolam + Sodium oxybate Contraindicated
- Amobarbital + Sodium oxybate Contraindicated
- Butorphanol + Sodium oxybate Contraindicated
- Chloral hydrate + Sodium oxybate Contraindicated
- Clonazepam + Sodium oxybate Contraindicated
- Clorazepate + Sodium oxybate Contraindicated
Frequently asked questions
Can I take Sodium oxybate with Valproic acid?
MediHelp rates the interaction as major. Sodium oxybate and Valproic acid 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. Valproate raises exposure to oxybate and increases the risk of excessive sedation, respiratory depression and coma. Both drugs depress the CNS. Labeling advises dose reduction of oxybate when valproate is added.
How serious is the interaction between Sodium oxybate and Valproic acid?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: When valproate is started in a patient stabilised on sodium oxybate, reduce the nightly oxybate dose by at least 20%. Monitor for sedation and respiratory depression and titrate the dose to response.
What other medicines interact with Valproic acid?
MediHelp also lists interactions of Valproic acid with, for example, Ertapenem, Imipenem / cilastatin / relebactam, Imipenem / cilastatin. The full list is on the Valproic acid page.
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