Valproate and Cimetidine Interaction

Drug interaction information between Valproate and Cimetidine.

Valproate and Cimetidine have a documented major interaction in FDA labeling.

FDA drug labeling documents a major-severity interaction between Valproate and Cimetidine. This page displays the available source-record category and label text. The category is not an individual risk estimate or medication-combination direction.

Drug A

Valproate

Anticonvulsant / Mood Stabilizer

Drug B

Cimetidine

H2 Receptor Antagonist

How They Interact

Cimetidine does not interfere with how the body breaks down or clears valproate. This means the amount of valproate in your blood should remain stable.

FDA Label Information

Cimetidine and Ranitidine Cimetidine and ranitidine do not affect the clearance of valproate.

Frequently Asked Questions

What SPL severity band is on file for Valproate + Cimetidine?

Compiled FDA labeling labels this pair major. That is a source-record field, not an individual medication-combination decision.

Which drug in this pair has the larger labeled-interaction portfolio?

Cimetidine has 77 labeled pairs on file vs Valproate's 41. In the major band specifically: Valproate has 2 (also Ranitidine); Cimetidine has 4 (also Levofloxacin, Posaconazole, Risperidone).

What mechanism field is on file for Valproate and Cimetidine?

Cimetidine does not interfere with how the body breaks down or clears valproate. This means the amount of valproate in your blood should remain stable.

Cimetidine carries more major-labeled pairs than Valproate

SPL source-record counts only. This page's band is major · classes on file: Valproate (Anticonvulsant / Mood Stabilizer); Cimetidine (H2 Receptor Antagonist).

Cimetidine has 4 major-labeled pairs vs Valproate's 2.

Valproate

2 major · 3 moderate · 36 minor · 41 total

Cimetidine

4 major · 10 moderate · 63 minor · 77 total

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.