Tiagabine and Valproate Interaction
Drug interaction information between Tiagabine and Valproate.
Tiagabine and Valproate have a documented minor interaction in FDA labeling.
FDA drug labeling documents a minor-severity interaction between Tiagabine and Valproate. This page displays the available source-record category and label text. The category is not an individual risk estimate or medication-combination direction.
How They Interact
Valproate pushes tiagabine off blood proteins, which increases the amount of active tiagabine in the body. Tiagabine also slightly lowers the levels of valproate.
FDA Label Information
Carbamazepine, phenytoin, primidone, and phenobarbital are generally classified as enzyme inducers; valproate and gabapentin are not. Valproate: Tiagabine causes a slight decrease (about 10%) in steady-state valproate concentrations. Valproate: The addition of tiagabine to patients taking valproate chronically had no effect on tiagabine pharmacokinetics, but valproate significantly decreased tiagabine binding in vitro from 96.3 to 94.8%, which resulted in an increase of approximately 40% in the free tiagabine concentration.
Tiagabine Also Interacts With
- Gabapentin minor
- Warfarin minor
- Digoxin minor
- Theophylline minor
- Cimetidine minor
Valproate Also Interacts With
- Ranitidine major
- Cimetidine major
- Clarithromycin moderate
- Lidocaine Topical moderate
- Risperidone moderate
Frequently Asked Questions
What SPL severity band is on file for Tiagabine + Valproate?
Compiled FDA labeling labels this pair minor. That is a source-record field, not an individual medication-combination decision.
Which drug in this pair has the larger labeled-interaction portfolio?
Valproate has 41 labeled pairs on file vs Tiagabine's 11. In the minor band specifically: Tiagabine has 11 (also Gabapentin, Warfarin, Digoxin, Theophylline); Valproate has 36 (also Aspirin, Clonazepam, Topiramate, Amitriptyline).
What mechanism field is on file for Tiagabine and Valproate?
Valproate pushes tiagabine off blood proteins, which increases the amount of active tiagabine in the body. Tiagabine also slightly lowers the levels of valproate.
Valproate carries more major-labeled pairs than Tiagabine
SPL source-record counts only. This page's band is minor · classes on file: Tiagabine (Anticonvulsant (GABA Reuptake Inhibitor)); Valproate (Anticonvulsant / Mood Stabilizer).
Valproate has 2 major-labeled pairs vs Tiagabine's 0. This page itself is in the minor band, not the major band.
0 major · 0 moderate · 11 minor · 11 total
- Other minor peers for Tiagabine
- Gabapentin
- Warfarin
- Digoxin
- Theophylline
2 major · 3 moderate · 36 minor · 41 total
- Other minor peers for Valproate
- Aspirin
- Clonazepam
- Topiramate
- Amitriptyline
Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. This registry does not provide individual medication-combination directions.
Read our methodology - how this data is sourced, computed, and verified.