Insulin overdose in dogs and cats: 28 cases (1986-1993).
OBJECTIVE
To characterize the frequency, medical history, clinical signs, methods of treatment, and outcome of insulin-induced hypoglycemia and to identify predisposing factors.


METHODS
Retrospective study.


METHODS
8 dogs and 20 cats with diabetes mellitus that developed hypoglycemia because of insulin overdose.


METHODS
Medical records of dogs and cats receiving insulin for treatment of diabetes mellitus were reviewed. Medical records of dogs and cats that had an episode of hypoglycemia were reviewed in detail.


RESULTS
Overdosing of insulin was more common in cats than in dogs. Median weight of diabetic cats that became hypoglycemic was significantly greater than that of the hospital population of diabetic cats at diagnosis. Eighty percent of cats that became hypoglycemic were receiving insulin doses > 6 U/injection, administered once or twice daily. Dose and type of insulin did not correlate with duration or severity of hypoglycemia. In 7 of 8 dogs and 10 of 20 cats, management factors or concurrent medical problems were considered to be predisposing causes for insulin overdose. Two dogs and 2 cats did not have clinical signs of hypoglycemia, despite documented low concentrations of glucose in their blood.


CONCLUSIONS
Diabetic cats, especially if obese, are at greater risk of insulin overdose than are diabetic dogs. The reason for overdose may not be evident. Diabetic dogs and cats may become hypoglycemic without developing autonomic warning signs of hypoglycemia, or these signs may not be recognized (hypoglycemia unawareness).
Whitley
N T
NT
Department of Medical Sciences, School of Veterinary Medicine, University of Wisconsin, Madison 53706-1102, USA.
Drobatz
K J
KJ
Panciera
D L
DL
D000818:Animals; D001786:Blood Glucose / Q000032:analysis / Q000378:metabolism; D002371:Cat Diseases / Q000097:blood / Q000139:chemically induced* / Q000453:epidemiology; D002415:Cats; D015984:Causality; D048909:Diabetes Complications; D003920:Diabetes Mellitus / Q000188:drug therapy / Q000662:veterinary*; D004283:Dog Diseases / Q000097:blood / Q000139:chemically induced* / Q000453:epidemiology; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D062787:Drug Overdose / Q000662:veterinary; D005260:Female; D007003:Hypoglycemia / Q000139:chemically induced / Q000453:epidemiology / Q000662:veterinary*; D007004:Hypoglycemic Agents / Q000009:adverse effects* / Q000627:therapeutic use; D015994:Incidence; D007328:Insulin / Q000009:adverse effects* / Q000627:therapeutic use; D008297:Male; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome
D001786:Blood Glucose; D007004:Hypoglycemic Agents; D007328:Insulin