Drug interactions
Metformin-sitagliptin + Zonisamide
Severity: Moderate
Metformin-sitagliptin and Zonisamide: moderate interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Zonisamide can cause metabolic acidosis, and combined use with metformin may increase the risk of lactic acidosis. The risk is higher with renal impairment or dehydration.
What this interaction means in plain words
Metformin-sitagliptin and Zonisamide can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Metformin-sitagliptin belongs to Endocrine; Zonisamide belongs to Central Nervous System.
Why it happens
Zonisamide weakly inhibits carbonic anhydrase, lowering serum bicarbonate, which adds to metformin's acidosis risk.
What to do
Monitor serum bicarbonate and renal function, and reassess therapy if persistent acidosis develops.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Metformin-sitagliptin and Zonisamide, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 7 days on the web. No card needed.
Other interactions of Metformin-sitagliptin
Other interactions of Zonisamide
- Zonisamide + Zuranolone Major
- Acetazolamide + Zonisamide Moderate
- Amisulpride + Zonisamide Moderate
- Amobarbital + Zonisamide Moderate
- Apalutamide + Zonisamide Moderate
- Asenapine transdermal + Zonisamide Moderate
Frequently asked questions
Can I take Metformin-sitagliptin with Zonisamide?
MediHelp rates the interaction as moderate. Metformin-sitagliptin and Zonisamide can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Zonisamide can cause metabolic acidosis, and combined use with metformin may increase the risk of lactic acidosis. The risk is higher with renal impairment or dehydration.
How serious is the interaction between Metformin-sitagliptin and Zonisamide?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor serum bicarbonate and renal function, and reassess therapy if persistent acidosis develops.
What other medicines interact with Metformin-sitagliptin?
MediHelp also lists interactions of Metformin-sitagliptin with, for example, Clozapine, Contrast media, Diatrizoate meglumine / diatrizoate. The full list is on the Metformin-sitagliptin page.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
