Metformin Hydrochloride's use in veterinary medicine
July 08, 2026
There is no FDA- or EMA-approved veterinary-labeled metformin product. In clinical practice, human-formulated metformin (immediate-release or extended-release tablets/solution, e.g. Glucophage® or generic) is prescribed extra-label by veterinarians for certain species.
🐱 Cats (Feline)
Indication: Occasionally trialed for non-insulin-dependent / type 2 diabetes mellitus (insulin-resistant diabetes) or obesity-related insulin resistance. Efficacy is limited; insulin ± SGLT2 inhibitors (bexagliflozin/Senvelgo®, velagliflozin) are now preferred.
Dosage (extra-label): 5–10 mg/kg or 25–50 mg/cat, PO, q12h (some sources start at 2–5 mg/kg).
Notes: Poor glycemic control reported in most cats; do not substitute for insulin in truly insulin-dependent diabetics.
🐶 Dogs (Canine)
Indication: Canine diabetes is predominantly type 1 (absolute insulin deficiency); metformin is NOT recommended as primary diabetes therapy. May be used as an adjunctto improve insulin sensitivity or manage dyslipidemia/insulin resistance secondary to hyperadrenocorticism (Cushing's disease).
Dosage (extra-label, adjunct only): 10–15 mg/kg, PO, q12h, starting low and titrating up weekly to minimize GI upset.
Notes: ~30–40% experience GI signs (vomiting, diarrhea, anorexia); contraindicated in renal impairment; consider B₁₂ monitoring with long-term use.
🐴 Horses / Ponies (Equine – EMS / ID)
Indication: Sometimes used in Equine Metabolic Syndrome (EMS) with insulin dysregulation to blunt post-prandial hyperglycemia and theoretically reduce laminitis risk. Bioavailability is very low (~4–7%); clinical benefit is debated.
Dosage (extra-label): 15–30 mg/kg, PO, q12h, ideally given 30–60 min before feeding.