Felis ISSN 2398-2950

Diabetes mellitus

Synonym(s): Sugar diabetes

Contributor(s): David Bruyette, Carmel Mooney, Nicki Reed


  • Common endocrine disease of middle-aged cat (approx. 1 in 400).
  • Cause: syndrome characterized by relative or absolute lack of insulin.
  • Signs: polyuria/polydipsia.
  • Diagnosis: glycosuria, persistent hyperglycemia, fructosamine.
  • Treatment: insulin, dietary management.
  • Prognosis: generally good if uncomplicated by concurrent condition.
    Print off the owner factsheet on Diabetes mellitus Diabetes mellitus and give to your client.



  • Type 1: inadequate secretion of insulin (immune-mediated, destruction of islet cells).
  • Type 2: resistance to insulin activity, eg obesity Obesity leading to relative lack of insulin (most common).
  • Type 3: antagonism to insulin (cortisol, progesterone, growth hormone, catecholamines, glucagon).
  • Inactivation of insulin (immune response).

Predisposing factors


  • Increasing age (may be due to increased presence of diseases causing insulin resistance in older cats).
  • Obesity:
    • Associated with indoor lifestyle.
  • Concurrent disease:
  • Drug therapy:
    • Progestagen therapy, eg megestrol acetate.
    • Glucocorticoids.
    • Cyclosporin may alter glucose homeostasis in humans and dogs (not documented in cats).
  • Genetic susceptibility.


  • Type 1: (insulin dependent - rare) destruction of beta cells (immune-mediated/congenital/neoplastic    →   failure of insulin response to hyperglycemia.
  • Type 2: (non-insulin dependent - most common) peripheral insulin resistance   →   increased insulin production required   →    glucose toxicity and increased amylin secretion    →   fall in insulin levels and islet amyloidosis    →   beta cell degeneration   →    type 1 diabetes.
  • Type 3: (concurrent disease - 5-10%) endocrinopathies or insulin antagonistic drugs   →   increased requirement for insulin   →   initial hyperinsulinemia   →   beta cell degeneration   →   type 1 diabetes.


  • Weeks to months.


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Further Reading


Refereed papers

  • Recent references from PubMed and VetMedResource.
  • Roomp K, Rand J S (2012) Evaluation of detemir in diabetic cats managed with a protocol for intensive glucose control. J Feline Med Surg 14 (8), 566-572 PubMed.
  • Scott-Moncreiff J C (2012) Insulin resistance in cats. Vet Clin N America Small Anim Pract 40 (2), 241-257 PubMed.
  • Marshall R D, Rand J S & Morton J (2009) Treatment of newly diagnosed diabetic cats with glargine insulin imporves glycemia control and results in higher probability of remission than protamine zinc and lente insulins. J Feline Med Surg 11 (8), 683-691 PubMed.
  • Roomp K, Rand J S (2009) Intensive blood glucose control is safe and effective in diabetic cats using home monitoring and treatment with glargine. J Feline Med Surg 11 (8), 668-682 PubMed.
  • Marshall R, Rand J, Morton J (2008) Insulin glargine has a long duration of effect following administration either once daily or twice daily in divided doses in healthy cats. J Feline Med Surg 10 (5), 488-494 PubMed.
  • Marshall R, Rand J, Morton J (2008) Glargine and protamine zinc insulin have a longer duration of action and result in lower mean daily glucose concentrations than lente insulin in healthy cats. J Vet Pharmacol Ther 31 (3), 205-212 PubMed.
  • Bennett N, Greco D S, Peterson M E et al (2006) Comparison of a low carbohydrate-low fiber diet and a moderate carbohydrate-high fiber diet in the management of feline diabetes mellitus. J Feline Med Surg (2), 73-84 PubMed.
  • Reusch C E, Tschour F, Kley S et al (2006) Diabetes mellitus in the cat: a review. Schweiz Arch Tierheilkd 148 (3), 130-138 PubMed.
  • Weaver K E, Rozanski E A, Mahony O M et al (2006) Use of glargine and lente insulins in cats with diabetes mellitus. J Vet Intern Med 20 (2), 234-8 PubMed.
  • Casella M, Hässig M & Reusch C E (2005) Home-monitoring of blood glucose in cats with diabetes mellitus: evaluation over a 4-month period. J Feline Med Surg (3), 163-171 PubMed.
  • Rand J S & Marshall R D (2005) Diabetes mellitus in cats. Vet Clin North Am Small Anim Pract 35 (1), 211-224 PubMed.
  • Ristic J M, Herrtage M E, Walti-Lauger S M et al (2005) Evaluation of a continuous glucose monitoring system in cats with diabetes mellitus. J Feline Med Surg (3), 153-162 PubMed.
  • Van de Maele I, Rogier N & Daminet S (2005) Retrospective study of owners' perception on home monitoriong of blood glucose in diabetic dogs and cats. Can Vet J 46 (8), 718-723 PubMed.
  • Kley S, Casella M & Reusch C E (2004) Evaluation of long-term home monitoring of blood glucose concentrations in cats with diabetes mellitus: 26 cases (1999-2002)JAVMA 225 (2), 261-266 PubMed.
  • Nelson R, Spann D, Elliott D et al (2004) Evaluation of the oral antihyperglycemic drug metformin in normal and diabetic cats. J Vet Intern Med 18 (1), 18-24 PubMed.
  • Rand J S, Fleeman L M, Farrow H A et al (2004) Canine and feline diabetes mellitus: nature or nuture? J Nutr 134 (8 Suppl), 2072S-2080S PubMed.
  • Thiess S, Becskei C, Tomsa K et al (2004) Effects of high carbohydrate and high fat diet on plasma metabolite levels and on i.v. glucose tolerance test in intact and neutered male cats. J Feline Med Surg (4), 207-218 PubMed.
  • Mazzaferro E M, Greco D S, Turner A S et al (2003) Treatment of feline diabetes mellitus using an alpha-glucosidase inhibitor and a low-carbohydrate diet. J Feline Med Surg (3), 183-189 PubMed.
  • Sennello K A, Schulman R L, Prosek R et al (2003) Systolic blood pressure in cats with diabetes mellitus. JAVMA 223 (2), 198-201 PubMed.
  • Wiedmeyer C E, Johnson P J, Cohn L A et al (2003) Evaluation of a continuous glucose monitoring system for use in dogs, cats, and horses. JAVMA 223 (7), 987-992 PubMed.
  • Bennett N (2002) Monitoring techniques for diabetes mellitus in the dog and the cat. Clin Tech Small Anim Pract 17 (2), 65-69 PubMed.
  • Zoran D L (2002) The carnivore connection to nutrition in cats. JAVMA 221 (11), 1559-1567 PubMed.
  • Zerbé C A (2001) What is so special about feline diabetes mellitus? J Feline Med Surg (2), 99-103 PubMed.
  • Behrend E N & Greco D S (2000) Feline diabetes mellitus - evaluation of treatment. Comp Cont Ed Pract Vet 22 (5), 440-453 VetMedResource.
  • Elliott D A, Feldman E C, Koblik P D et al (2000) Prevalence of pituitary tumours among diabetic cats with insulin resistance. JAVMA 216 (11), 1765-1768 PubMed.
  • Hoenig M, Hall G, Ferguson D et al (2000) A feline model of experimentally induced islet amyloidosis. Am J Pathol 157 (6), 2143-2150 PubMed.
  • Hoenig M, Reusch C & Peterson M E (2000) Beta cell and insulin antibodies in treated and untreated diabetic cats. Vet Immunol Immunopathol 77 (1-2), 93-102 PubMed.
  • Nelson R W (2000) Oral medications for treating diabetes mellitus in dogs and cats. JSAP 41 (11), 486-490 PubMed.
  • Nelson R W (2000) Selected topics in the management of diabetes mellitus in cats. Journal Fel Med Surg (2), 101-104 PubMed.
  • Norman E J & Mooney C T (2000) Diagnosis and management of diabetes mellitus in five cats with somatotrophic abnormalities. JFMS (4), 183-190 PubMed.
  • Feldhahn J R, Rand J S, Kinnaird E (1999) The effect of interday variation and a short term stressor on insulin sensitivity in clinically normal cats. J Fel Med Surg 1 (4), 233-240 PubMed.
  • Foldhahn J R & Martin G (1999) Insulin sensitivity in normal and diabetic cats. J Feline Med Surg (2), 107-15 PubMed.
  • Godfrey D R (1999) What is your diagnosis? Non-ketotic hyperosmolar diabetes mellitus. JSAP 40 (9), 409, 450 PubMed.
  • Greco D S (1999) Insulin therapy in cats. JAAHA 35 (4), 269-270 PubMed.
  • Martin G J W, Rand J S (1999) Food intake and blood glucose in normal and diabetic cats fed ad libitum. J Fel Med Surg (4), 241-251 PubMed.
  • Nelson R W, Griffey S M, Feldman E C et al (1999) Transient clinical diabetes mellitus in cats - 10 cases (1989-1991). J Vet Intern Med 13 (1), 28-35 PubMed.
  • Rand J (1999) Current understanding of feline diabetes. Part 1, Pathogenesis. J Feline Med Surg (3), 143-53 PubMed.
  • Feldman E C, Nelson R W & Feldman M S (1997) Intensive 50-week evaluation of glipizide administration in 50 cats with previously untreated diabetes mellitus. JAVMA 210 (6), 772-777 PubMed.
  • Kraus M S, Calvert C A, Jacobs G J et al (1997) Feline diabetes mellitus a retrospective mortality study of 55 cats (1982-1994). JAAHA 33 (2), 107-111 PubMed.
  • Rand J S, Bobbermien L M, Hendrikz J K et al (1997) Over-representation of Burmese cats with diabetes mellitus in Australia. Aust Vet J 75 (6), 402-405 PubMed.
  • Crenshaw K L & Peterson M E (1996) Pre-treatment clinical and laboratory evaluation of cats with diabetes mellitus 104 cases (1992-1994). JAVMA 209 (5), 943-949 PubMed.
  • Crenshaw K L, Peterson M E, Heeb L A et al (1996) Serum fructosamine concentrations as an index of glycemia in cats with diabetes mellitus and stress hyperglycemia. JVIM 10 (6), 360-364 PubMed.
  • Carlson R A (1994) Hyperosmolar nonketotic diabetes mellitus in a cat. Feline Pract 22 (3), 20-24 VetMedResource.
  • Kirk C A, Feldman E C & Nelson R W (1993) Diagnosis of naturally acquired Type I and Type II diabetes mellitus in the cat. Am J Vet Res 54 (3), 463-467 PubMed.
  • Miller A B, Nelson R W, Kirk C A et al (1992) Effect of glipizide on serum insulin and glucose concentrations in healthy cats. Res Vet Sci 52 (2), 177-181 PubMed.