Exogenous insulin that binds to insulin receptors, facilitating glucose uptake into cells, glycogen synthesis, and protein synthesis while inhibiting gluconeogenesis and lipolysis
At a glance
Class
Intermediate-acting insulin (isophane suspension)
Storage
MUST be refrigerated (2-8°C). Do NOT freeze. Gently roll before use — do NOT shake. Discard if discoloured or clumped. In-use vials: refrigerate, use within 28 days.
Dosing
Diabetes mellitus
Max dose
40 IU/dose; 80 IU/day
Duration: Lifelong; titrate based on blood glucose curves every 1-2 weeks
Diabetes mellitus
Max dose
10 IU/dose; 20 IU/day
Duration: Lifelong (unless diabetic remission); start conservative and titrate
Diabetic ketoacidosis (DKA) — transition from regular insulin
Max dose
6 IU/dose; 12 IU/day
Duration: Start when eating and stable; transition from CRI regular insulin
Safety
Absolute contraindications — do not use
Concurrent corticosteroids
Corticosteroids cause insulin resistance — significantly higher insulin doses required
Concurrent progesterone (intact females)
Diestrus/progesterone causes insulin resistance — spay recommended for diabetic females
Inconsistent feeding
Insulin must be given with meals to prevent hypoglycaemia
Adverse effects
Common
Hypoglycaemia (most common and dangerous)
Weight gain
Injection site reactions
Serious
Severe hypoglycaemia (seizures, coma, death)
Somogyi rebound hyperglycaemia
Insulin-induced hypokalaemia
Blood glucose curves (every 1-2 weeks until stable, then monthly)Fructosamine every 2-4 weeksBody weightWater intake / urine outputClinical signs (PU/PD/PP)Spot blood glucose before insulin dose
Interactions
No documented interactions.
FAQs
Frequently asked questions
›What is Insulin (NPH / Isophane)?
Insulin (NPH / Isophane) is a intermediate-acting insulin (isophane suspension) used in pets. Exogenous insulin that binds to insulin receptors, facilitating glucose uptake into cells, glycogen synthesis, and protein synthesis while inhibiting gluconeogenesis and lipolysis
›What is Insulin (NPH / Isophane) used for in pets?
Insulin (NPH / Isophane) is used in veterinary medicine for: Diabetes mellitus; Diabetic ketoacidosis (DKA) — transition from regular insulin.
›What is the Insulin (NPH / Isophane) dose for dogs?
For dogs, Insulin (NPH / Isophane) is typically dosed as follows — Diabetes mellitus: 0.25–1 IU/kg SC BID. Always consult your veterinarian for a dose tailored to your pet's weight, age, and condition.
›What is the Insulin (NPH / Isophane) dose for cats?
For cats, Insulin (NPH / Isophane) is typically dosed as follows — Diabetes mellitus: 0.25–1 IU/kg SC BID; Diabetic ketoacidosis (DKA) — transition from regular insulin: 0.25–0.5 IU/kg SC BID. Always consult your veterinarian for a dose tailored to your pet's weight, age, and condition.
›What are the side effects of Insulin (NPH / Isophane)?
Common: Hypoglycaemia (most common and dangerous), Weight gain, Injection site reactions. Serious (call your vet immediately): Severe hypoglycaemia (seizures, coma, death), Somogyi rebound hyperglycaemia, Insulin-induced hypokalaemia.
›Does Insulin (NPH / Isophane) need a prescription?
Yes. Insulin (NPH / Isophane) is a prescription medication and should only be administered under veterinary supervision.
›When should Insulin (NPH / Isophane) not be used?
Do not use Insulin (NPH / Isophane) if: Hypoglycaemia.
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.
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