Glipizide: veterinary dose and monograph

At a glance

Drug class

Veterinary drug

Also known as

Glucotrol, Glynase (glipizide), Glytop

Species with doses

Cats

Routes

PO

Last reviewed

1 October 2026

Indications

• Feline non-insulin-dependent (type-2-like) diabetes mellitus — stable, well-selected cats
• Owner-declined-insulin cases where oral therapy is attempted (with informed limitations)

Glipizide dose by species

Doses are per administration unless stated. mg/kg doses scale with body weight; per-animal, per-quarter and infusion-rate doses are shown as the reference writes them.

Cats

• Type-2 diabetes mellitus (non-ketotic, well cat): Papich 5e: 2.5–7.5 mg per cat q12h PO — usually 2.5 mg initially, then 5 mg q12h. Plumb’s p.574: 2.5 mg twice daily with food, check glucose every 3–4 h for the first 12–18 h, increase to 5 mg twice daily after 2 weeks if still hyperglycaemic (Herrtage 2009); maximum 7.5 mg twice daily (Feldman 2005). Switch to insulin if ketotic, ill, or glucose >270 mg/dL after 1–2 months. Fewer than half of cats respond.

Contraindications

Diabetic ketoacidosis or any unstable/ill diabetic (use insulin). Insulin-dependent diabetes / non-functional β-cells. Significant hepatic or renal impairment. Pregnancy. Sulfonamide hypersensitivity. Known hypersensitivity. Not for dogs.

Species-specific warnings

Cats: Only for non-ketotic, stable type-2-like diabetics; if the cat is unwell, ketotic or losing weight, switch to insulin. Stop if hepatotoxicity develops.

Adverse effects

• Hypoglycaemia
• Vomiting/anorexia (give with food)
• Hepatotoxicity (raised liver enzymes, icterus) — may necessitate stopping
• Does not halt ongoing β-cell loss; many cats ultimately need insulin

Drug interactions

• Other hypoglycaemics / insulin: additive hypoglycaemia
• Beta-blockers: mask hypoglycaemia signs and may impair recovery
• Corticosteroids / progestins: antagonise glucose control (raise glucose)
• Hepatically metabolised — CYP interactions can alter levels

Pregnancy and lactation

Avoid in pregnancy (use insulin if a diabetic queen requires glycaemic control).

Monitoring

• Blood glucose / fructosamine and clinical signs (PU/PD, weight, appetite)
• Hypoglycaemia signs (warn owner)
• Liver enzymes (hepatotoxicity)
• Reassess need to switch to insulin if control is inadequate

Toxicity and overdose

The main acute risk is HYPOGLYCAEMIA (weakness, ataxia, seizures, coma) — including from accidental overdose or a cat that eats poorly after dosing. Chronic concern is hepatotoxicity. Overdose of sulfonylureas can cause prolonged, recurrent hypoglycaemia.

Management: Treat hypoglycaemia: oral glucose/Karo syrup if conscious, IV dextrose bolus then a dextrose CRI for sustained/severe cases (sulfonylurea hypoglycaemia can be prolonged and recurrent — monitor for hours). Octreotide can blunt refractory sulfonylurea-induced insulin release. Supportive care; monitor glucose closely and check liver values.

Clinical pearls

• An oral option ONLY for stable feline type-2-like diabetes with residual β-cell function — insulin remains more effective and is required for sick/ketotic cats
• Always give with food and counsel owners on hypoglycaemia (and to skip a dose if the cat isn't eating)
• Watch liver enzymes — hepatotoxicity is a recognised reason to discontinue
• Octreotide is a useful adjunct for refractory sulfonylurea overdose hypoglycaemia
• Not for dogs (canine diabetes is insulin-dependent)

Mechanism of action

A sulfonylurea that binds the SUR1 subunit of ATP-sensitive potassium channels on pancreatic β-cells, closing them; the resulting depolarisation opens voltage-gated calcium channels and triggers insulin secretion. It therefore augments endogenous insulin release and requires functioning β-cells — it cannot work in true insulin-deficient diabetes. Extra-pancreatic effects on insulin sensitivity are minor.

Formulations and products

• 2.5 mg tablet
• 5 mg tablet
• Glynase — 5 mg tablet, Tablet (human-label)
• Glytop — 2.5 / 5 mg tablet, Tablet (human-label)

Storage

Tablets: 15–30 °C, dry, protect from light/moisture.

Before you use this dose

Reference doses for veterinary professionals. Confirm the dose against the product label, the patient’s condition, current guidance and local regulations before use; the attending veterinarian remains responsible for every clinical decision.

Other hormones, emergency drugs, supplements and other drugs

• Flumazenil
• Fluoxetine
• Fluticasone (Inhaled)
• Fomepizole (4-MP)
• Glycopyrrolate
• Gonadorelin (GnRH)
• Heparin (Unfractionated)
• Hetastarch (Hydroxyethyl Starch)

Frequently asked questions