Topiramate and Zonisamide Interaction
Drug interaction information between Topiramate and Zonisamide.
Topiramate and Zonisamide have a documented moderate interaction in FDA labeling.
FDA drug labeling documents a moderate-severity interaction between Topiramate and Zonisamide. 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
Both drugs block the same enzyme, which can make your blood too acidic. This combination also makes it more likely that you will develop kidney stones.
FDA Label Information
7.2 Other Carbonic Anhydrase Inhibitors Concomitant use of topiramate, a carbonic anhydrase inhibitor, with any other carbonic anhydrase inhibitor (e.g., zonisamide or acetazolamide) may increase the severity of metabolic acidosis and may also increase the risk of kidney stone formation.
Topiramate Also Interacts With
- Alogliptin moderate
- Ertugliflozin moderate
- Hydrochlorothiazide minor
- Amitriptyline minor
- Pioglitazone minor
Zonisamide Also Interacts With
- Alogliptin moderate
- Ertugliflozin moderate
- Carbamazepine minor
- Empagliflozin minor
- Empagliflozin/Linagliptin minor
Frequently Asked Questions
What SPL severity band is on file for Topiramate + Zonisamide?
Compiled FDA labeling labels this pair moderate. That is a source-record field, not an individual medication-combination decision.
Which drug in this pair has the larger labeled-interaction portfolio?
Topiramate has 30 labeled pairs on file vs Zonisamide's 13. In the moderate band specifically: Topiramate has 3 (also Alogliptin, Ertugliflozin); Zonisamide has 3 (also Alogliptin, Ertugliflozin).
What mechanism field is on file for Topiramate and Zonisamide?
Both drugs block the same enzyme, which can make your blood too acidic. This combination also makes it more likely that you will develop kidney stones.
Topiramate's labeled portfolio outnumbers Zonisamide
SPL source-record counts only. This page's band is moderate · classes on file: Topiramate (Anticonvulsant); Zonisamide (Anticonvulsant (Sulfonamide)).
0 major · 3 moderate · 27 minor · 30 total
- Other moderate peers for Topiramate
- Alogliptin
- Ertugliflozin
0 major · 3 moderate · 10 minor · 13 total
- Other moderate peers for Zonisamide
- Alogliptin
- Ertugliflozin
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.