Cat Insulin Dose Calculator
Feline diabetes mellitus requires insulin therapy in most cases, and determining the correct starting dose is the first critical step. The standard starting dose recommended by veterinary internists is 0.25 units per kilogram of body weight, administered subcutaneously twice daily (every 12 hours). This conservative initial dose is designed to begin glucose regulation while minimizing the risk of hypoglycemia. The dose is then adjusted based on serial glucose curves until adequate glycemic control is achieved. This calculator computes the starting dose based on body weight and also shows the dose range (0.25-0.5 units/kg) that veterinarians typically consider for initial therapy. All insulin therapy must be prescribed and monitored by a licensed veterinarian.
Feline insulin dosing formula
Dose per injection (units) = Dose rate (units/kg) x Body weight (kg)
Daily total (units/day) = Dose per injection x 2 (twice daily)
Starting range: 0.25 to 0.50 units/kg per injection
The 0.25 units/kg starting dose is the standard conservative initial dose. Doses above 2 units per injection are rarely needed in cats; high doses increase hypoglycemia risk and may indicate insulin resistance requiring investigation.
Monitoring diabetic cats on insulin
- Perform a glucose curve 1-2 weeks after starting or changing dose: check glucose every 2 hours over 12-24 hours.
- Target nadir glucose: 80-150 mg/dL (4.4-8.3 mmol/L) with no hypoglycemia.
- Never give insulin if the cat is not eating; contact your vet for guidance on skipped meals.
- Store insulin as directed; glargine is refrigerated but not frozen.
- Use the correct syringe for your insulin concentration (U-100 syringes for U-100 insulin; U-40 syringes for U-40 insulin).
Cat insulin dose calculator: frequently asked questions
What is the standard starting insulin dose for cats?
The standard starting dose for diabetic cats is approximately 0.25 units per kg of body weight, given subcutaneously twice daily (every 12 hours). This conservative starting dose minimizes the risk of hypoglycemia while beginning glucose regulation. Dose adjustments are based on serial glucose curves.
What type of insulin is used in cats?
Glargine (Lantus) and ProZinc (protamine zinc insulin) are among the most commonly used insulins in diabetic cats in the US. Glargine is a human long-acting analog that works well in cats. The choice of insulin affects dose timing and concentration. Always use the specific concentration (U-100 or U-40) for your insulin brand.
How do I adjust the dose after starting?
Dose adjustments are made based on glucose curves performed at home with a glucometer or at the veterinary clinic. A typical goal is a nadir (lowest glucose) between 80-150 mg/dL. Dose is increased by 0.5-1 unit increments every 1-2 weeks if control is inadequate, with close monitoring for hypoglycemia.
What is hypoglycemia and how dangerous is it in cats?
Hypoglycemia (blood glucose below 60-70 mg/dL) is the most serious complication of insulin therapy. Signs include weakness, ataxia, seizures, and coma. Immediate treatment requires rubbing corn syrup on the gums and seeking emergency veterinary care. Home glucose monitoring is strongly recommended for all insulin-treated cats.
Can diabetic cats go into remission?
Yes, approximately 25-50% of diabetic cats achieve diabetic remission (normal glucose without insulin) if early aggressive treatment is used, typically with glargine or detemir insulin, dietary management (high-protein, low-carbohydrate food), and consistent monitoring. Remission is more likely in recently diagnosed cats.
Official sources
- American Animal Hospital Association (AAHA) Diabetes Management Guidelines: AAHA Homepage.
- FDA Center for Veterinary Medicine: Animal and Veterinary.
Reviewed by the CalculatorHub team, edited by James Graham, 15 June 2026. See our methodology.