Does Metformin Interact With Topiramate?
carbonic anhydrase inhibitors such as topiramate), age 65 years old or greater, having a radiological study with contrast, surgery and other procedures, hypoxic states (e.g., acute congestive heart failure), excessive alcohol intake, and hepatic impairment.
Severity: Moderate
Severity basis: boxed warning (keywords: boxed warning). Combining Metformin (Biguanide antidiabetic) and Topiramate (Anticonvulsant) is classified as a moderate interaction.
What to Do
Use this combination with caution. Your prescriber may monitor you more closely or adjust doses.
How This Interaction Works
Interactions like this one can happen when two medicines have overlapping effects, or when one changes how the other is absorbed, broken down, or cleared from the body. Metformin is a biguanide antidiabetic and Topiramate is a anticonvulsant; together they are documented as a moderate interaction. How much this matters depends on your dose, your other medications, and your overall health.
If You Take Both Medications
If you have been prescribed both Metformin and Topiramate, do not start, stop, or change either medication on your own — some medicines are unsafe to stop suddenly. Tell your prescriber and pharmacist that you take both so they can decide whether the combination is right for you, adjust the dose, monitor you more closely, or suggest an alternative.
From the FDA Label
carbonic anhydrase inhibitors such as topiramate), age 65 years old or greater, having a radiological study with contrast, surgery and other procedures, hypoxic states (e.g., acute congestive heart failure), excessive alcohol intake, and hepatic impairment.
Source: FDA structured product labeling (set_id 011de1a5-1ac0-4831-9e8d-26ec79ba2205).
Check these against your full medication list in our free Interaction Checker
Frequently Asked Questions
Can you take Metformin and Topiramate together?
Metformin and Topiramate have a documented moderate interaction. Use this combination with caution. Your prescriber may monitor you more closely or adjust doses.
How serious is the Metformin and Topiramate interaction?
It is classified as a moderate interaction, based on the FDA label's boxed warning (keywords: boxed warning). A moderate interaction can be clinically meaningful and usually calls for monitoring or a dose adjustment.
What should I do if I'm taking both Metformin and Topiramate?
If you have been prescribed both Metformin and Topiramate, do not start, stop, or change either medication on your own — some medicines are unsafe to stop suddenly. Tell your prescriber and pharmacist that you take both so they can decide whether the combination is right for you, adjust the dose, monitor you more closely, or suggest an alternative.
This information is educational — not medical advice.
This page is provided for general educational purposes and summarizes publicly available data from sources such as the U.S. Food & Drug Administration. It is not a substitute for the judgment of a licensed clinician and should not be used to start, stop, or change any medication. It may be incomplete or out of date, and individual circumstances vary. Always talk with your prescriber or pharmacist about your specific medications and health conditions. If you think you may have a medical emergency, call 911.