Drug Interaction Report

Metformin and Dorzolamide: Interaction Details

A pharmacist-reviewed analysis of the Metformin and Dorzolamide interaction: the documented clinical effects, severity rating, onset, mechanism, and management considerations, with cited references throughout.

AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature

Metformin

Fortamet® Glucophage Glucophage® Glumetza Glumetza® Riomet Riomet® Trijardy® (as a combination product containing Empagliflozin, Linagliptin, Metformin)
+

Dorzolamide

No brand names on record
Dr. Brian Staiger, PharmD, BCPS
Medically reviewed by
Dr. Brian Staiger, PharmD, BCPS
Updated Aug 8, 2026
Editorial policy · Data sources
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Interaction severity
Major
Potentially serious — often needs a change or close monitoring.
How we grade severity & evidence

Severity levels

  • Contraindicated: These should generally not be used together.
  • Major: Potentially serious — often needs a change or close monitoring.
  • Moderate: Can be significant — usually manageable with monitoring.
  • Minor: Usually limited clinical impact.

Evidence grades

  • Established: Well documented — supported by controlled studies or strong clinical data.
  • Probable: Good supporting evidence, though not definitively proven.
  • Suspected: Some evidence suggests this interaction, but it is not well established.
  • Possible: Limited or conflicting evidence; the interaction may occur.
  • Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.

Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.

Of 378 documented Metformin interactions, 99 are rated major — including this one.
Worried about symptoms right now? Contact your pharmacist or prescriber, or call Poison Control at 1-800-222-1222 (US). Call 911 for an emergency.
Onset
unspecified
Evidence
probable
Severity
Major

What happens

An increased risk of lactic acidosis and reduced serum bicarbonate

Interaction Deep Dive

Carbonic anhydrase inhibitors may reduce serum bicarbonate and induce non-anion gap, hyperchloremic metabolic acidosis. Concomitant use of carbonic anhydrase inhibitors with metFORMIN may increase the risk of lactic acidosis. Consider more frequent monitoring of these patients213. In a drug interaction study, coadministration of metFORMIN 500 mg every 12 hours with topiramate 100 mg every 12 hours may increase the exposure of metFORMIN. The geometric mean ration of metFORMIN with or without topiramate was 1.25 and 1.17 for AUC (0 to inf) and Cmax respectively 32.

Why it happens (mechanism)

Induction of non-anion gap; induction of hyperchloremic metabolic acidosis

Literature reports

1 report — tap to read

a) Coadministration of metFORMIN 500 mg every 12 hours with topiramate 100 mg every 12 hours may increase the exposure of metFORMIN. The geometric mean ration of metFORMIN with or without topiramate was 1.25 and 1.17 for AUC (0 to inf) and Cmax respectively 32.

Common questions

Can I take Metformin and Dorzolamide together?

An increased risk of lactic acidosis and reduced serum bicarbonate Always confirm with your pharmacist or prescriber before making any change.

How serious is the Metformin and Dorzolamide interaction?

It is rated major. Potentially serious — often needs a change or close monitoring.

How quickly could this interaction happen?

The documented onset is "unspecified". The timing of this interaction is not well characterized.

How strong is the evidence for this interaction?

The evidence is graded "probable". Good supporting evidence, though not definitively proven.

Questions for your pharmacist

  • Does my dose of Metformin or Dorzolamide need adjusting while I take them together?
  • What symptoms should prompt me to call you or my prescriber right away?
  • Does the timing of my doses matter for this combination?
  • Is there a safer alternative to one of these medications for me?

References (3)

  1. Product Information: SYNJARDY(R) oral tablets, empagliflozin metformin hydrochloride oral tablets. Boehringer Ingelheim Pharmaceuticals Inc (per FDA), Ridgefield, CT, 2025. DailyMed
  2. Product Information: ZITUVIMET(R) XR oral extended release tablets, sitagliptin metformin HCl oral extended-release tablets. Zydus Pharmaceuticals (USA) Inc. (per FDA), Pennington, NJ, 2024. DailyMed
  3. Product Information: KAZANO oral tablets, alogliptin, metformin hydrochloride oral tablets. Takeda Pharmaceuticals America Inc (per FDA), Lexington, MA, 2023. DailyMed
Was this write-up helpful?
Metformin

Keep reading about Metformin

All Metformin interactions (378) Metformin drug information
Also serious with: Cimetidine Digoxin Insulin Glulisine (Rdna Origin) Injection Arimoclomol
Dorzolamide

Keep reading about Dorzolamide

All Dorzolamide interactions (4)
Also serious with: Aspirin Aspirin Rectal Memantine
Beyond drug–drug

These medications also interact with supplements

Prescription drugs aren't the whole picture — herbal and dietary supplements can interact with them too. From the evidence-graded Natural Medicines database:

Metformin + Activated Charcoal Siberian Cocklebur Acai African Wild Potato Agaricus Mushroom Agmatine Agrimony Alfalfa + 250 more
Dorzolamide + Activated Charcoal Biofeedback Coffee Charcoal Dendrobium European Mandrake Ginkgo Glucomannan Guar Gum + 15 more

major · moderate · minor — check everything you take with our drug–supplement interaction checker.

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This information is for education, not a substitute for professional medical advice. Do not start, stop, or change any medication without talking to your pharmacist or prescriber.