Lorazepam and Valproate Interaction
Drug interaction information between Lorazepam and Valproate.
Lorazepam and Valproate have a documented minor interaction in FDA labeling.
FDA drug labeling documents a minor-severity interaction between Lorazepam and Valproate. Major interactions are generally avoided, moderate ones may need monitoring or a dose adjustment, and minor ones are usually low-risk. This page shows the documented mechanism and guidance. Label-documented interactions are not a complete safety review, so always confirm your own medications with a pharmacist or doctor. Educational information, not medical advice.
How They Interact
Valproate slows down how fast the liver breaks down lorazepam, which causes the drug to build up in the body.
What To Do
Your doctor should reduce your lorazepam dose by about half when taking these two medicines together.
FDA Label Information
Concurrent administration of lorazepam with valproate results in increased plasma concentrations and reduced clearance of lorazepam. Lorazepam dosage should be reduced to approximately 50% when coadministered with valproate. The effects of probenecid and valproate on lorazepam may be due to inhibition of glucuronidation.
Lorazepam Also Interacts With
- Clozapine minor
- Probenecid minor
- Theophylline minor
- Aripiprazole minor
- Clarithromycin minor
Valproate Also Interacts With
- Ranitidine major
- Cimetidine major
- Clarithromycin moderate
- Lidocaine Topical moderate
- Risperidone moderate
Frequently Asked Questions
Can I take Lorazepam and Valproate together?
This is a minor interaction. Your doctor should reduce your lorazepam dose by about half when taking these two medicines together.
How serious is the interaction between Lorazepam and Valproate?
This interaction is classified as "minor" severity by the FDA. Minor interactions are unlikely to cause significant problems but should still be mentioned to your healthcare provider.
Why do Lorazepam and Valproate interact?
Valproate slows down how fast the liver breaks down lorazepam, which causes the drug to build up in the body.
Understanding the Lorazepam and Valproate Interaction
FDA-approved prescribing information for these two drugs flags their combination as a minor-severity interaction. Lorazepam belongs to the Benzodiazepine class and Valproate belongs to the Anticonvulsant / Mood Stabilizer class - two categories that can collide when co-prescribed. The mechanism described in FDA labeling is: Valproate slows down how fast the liver breaks down lorazepam, which causes the drug to build up in the body. Severity tiers matter: major flags generally advise avoidance, moderate flags often require monitoring or dose adjustment, and minor flags may only call for awareness.
Context around a specific patient determines real-world impact. Lorazepam has 11 total documented interactions on file in this dataset, and Valproate has 41. Each additional medication compounds the interaction surface, which is why pharmacists run full-profile checks rather than evaluating one pair at a time. FDA-derived guidance for this pair is: Your doctor should reduce your lorazepam dose by about half when taking these two medicines together. Timing of doses, renal and hepatic function, age, and other concurrent prescriptions all shape whether a labeled interaction matters clinically.
An interaction flag is not a verdict. A large share of labeled interactions are managed routinely in clinical practice, the fix may be as simple as spacing doses or adding a monitoring test. Others require the prescriber to choose a different medication entirely. This page surfaces FDA-sourced labeling and openFDA data for educational purposes only; it is not medical advice and cannot account for your full clinical picture. Never start, stop, or adjust either Lorazepam or Valproate based on a web page, speak with your prescriber or pharmacist before making any change.
Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. Always consult your healthcare provider about drug interactions.
Read our methodology - how this data is sourced, computed, and verified.