Home/Medicines/Metformin
All medicines

Metformin

Prescription
Biguanide Antidiabetic Agent
Last reviewed 21 Apr 2026 · PetCare.AI Editorial Team
Species
Dog, Cat
Brands
1 available
Interactions
2 documented
Formulations
3

Mechanism of action

Reduces hepatic glucose production (gluconeogenesis), enhances peripheral insulin sensitivity, and reduces intestinal glucose absorption. Does not stimulate insulin secretion — no hypoglycemia risk when used alone. Also has anti-inflammatory and anti-neoplastic properties.

At a glance

Class
Biguanide Antidiabetic Agent
Schedule
Prescription
Storage
Store at room temperature below 30°C, protect from light and moisture

Dosing

🐕

Dog

Off-label for insulin-resistant diabetes (adjunct to insulin)
Dose
25–50 mg/dog
Route
PO
Frequency
q12h
🐈

Cat

Investigational for feline Type 2 diabetes as adjunct to insulin or glipizide
Dose
25–50 mg/cat
Route
PO
Frequency
q12h

Formulations

💊

Other — 3

Strength
—
Strength
—
Strength
—

Storage

Store at room temperature below 30°C, protect from light and moisture

Safety

Monitoring parameters

Blood glucose curvesRenal function (creatinine)Lactate (if clinical suspicion)GI toleranceB12 levels with chronic use

Interactions

Major — 1

Prednisolone
major
Corticosteroids directly antagonize metformin's insulin-sensitizing effect by increasing hepatic gluconeogenesis and peripheral insulin resistance.
Management: Avoid steroids with metformin. If unavoidable, metformin alone will be inadequate — insulin therapy likely needed.

Moderate — 1

Furosemide
moderate
Furosemide may reduce metformin renal clearance, increasing metformin levels and lactic acidosis risk. Furosemide-induced dehydration further increases risk.
Management: Monitor renal function and hydration. Lactic acidosis risk increases with dehydration or renal impairment.

Brands

Other markets

Glucophage

FAQs

Frequently asked questions

›What is Metformin?
Metformin is a biguanide antidiabetic agent used in pets. Reduces hepatic glucose production (gluconeogenesis), enhances peripheral insulin sensitivity, and reduces intestinal glucose absorption. Does not stimulate insulin secretion — no hypoglycemia risk when used alone. Also has anti-inflammatory and anti-neoplastic properties.
›What is Metformin used for in pets?
Metformin is used in veterinary medicine for: Off-label for insulin-resistant diabetes (adjunct to insulin); Investigational for feline Type 2 diabetes as adjunct to insulin or glipizide.
›What is the Metformin dose for dogs?
For dogs, Metformin is typically dosed as follows — Off-label for insulin-resistant diabetes (adjunct to insulin): 25–50 mg/dog PO q12h. Always consult your veterinarian for a dose tailored to your pet's weight, age, and condition.
›What is the Metformin dose for cats?
For cats, Metformin is typically dosed as follows — Investigational for feline Type 2 diabetes as adjunct to insulin or glipizide: 25–50 mg/cat PO q12h. Always consult your veterinarian for a dose tailored to your pet's weight, age, and condition.
›Does Metformin need a prescription?
Yes. Metformin is a prescription medication and should only be administered under veterinary supervision.

References

References

Textbooks & handbooks

  • Plumb, D.C. Plumb's Veterinary Drug Handbook. 10th ed., Wiley-Blackwell, 2023.
  • Vail, D.M., Thamm, D.H., & Liptak, J.M. (eds.). Withrow & MacEwen's Small Animal Clinical Oncology. 6th ed., Saunders/Elsevier, 2020.
  • Riviere, J.E., & Papich, M.G. (eds.). Veterinary Pharmacology and Therapeutics. 10th ed., Wiley-Blackwell, 2018.
  • National Research Council. Nutrient Requirements of Dogs and Cats. National Academies Press, Washington DC, 2006.
  • The Merck Veterinary Manual. Merck & Co., Online edition. https://www.merckvetmanual.com/

Clinical guidelines & consensus

  • Fletcher, D.J., Boller, M., Brainard, B.M., et al. "RECOVER Evidence and Knowledge Gap Analysis on Veterinary CPR." Journal of Veterinary Emergency and Critical Care, 2012;22(S1):S102–S131.
  • American Animal Hospital Association. 2018 AAHA Diabetes Management Guidelines for Dogs and Cats. AAHA Press.

Journals & peer-reviewed studies

  • Hogan, D.F., Fox, P.R., Jacob, K., et al. "Secondary prevention of cardiogenic arterial thromboembolism in the cat: The FAT CAT study." Journal of Veterinary Cardiology, 2015;17(Suppl 1):S306–S317.
  • Boswood, A., Häggström, J., Gordon, S.G., et al. "Effect of Pimobendan in Dogs with Preclinical Myxomatous Mitral Valve Disease and Cardiomegaly: The EPIC Study — A Randomized Clinical Trial." Journal of Veterinary Internal Medicine, 2016;30(6):1765–1779.
  • ASPCA Animal Poison Control Center. Toxicology and Poison Management Guidelines. American Society for the Prevention of Cruelty to Animals. https://www.aspca.org/pet-care/animal-poison-control

Regulatory & approvals

  • Central Drugs Standard Control Organisation (CDSCO), Government of India. Veterinary Drug Approval Registry, 1969–2026. Directorate General of Health Services. https://cdsco.gov.in/

Databases

  • Washington State University, College of Veterinary Medicine. Veterinary Clinical Pharmacology Laboratory (VCPL) — MDR1 Multidrug Sensitivity Database. https://vcpl.vetmed.wsu.edu/
Educational reference only
This information is provided for educational purposes and is not a substitute for professional veterinary advice, diagnosis, or treatment. Always consult a qualified veterinarian before administering any medication to your pet. Find a vet near you →