Effects of Medetomidine on Serum Insulin and Plasma Glucose Concentrations in Clinically Normal Dogs

Objective: To determine the effects of medetomidine, administered i.v., on serum insulin and plasma glucose concentrations in clinically normal dogs.

Animals: 6 healthy adult Beagles.

Procedure: Dogs were randomly assigned to each of 3 treatments in a prospective cross-over study design. Serum insulin and plasma glucose concentrations were determined before and 20, 40, 60, 120, 180, 240, 300, 360, 420, and 480 minutes after i.v. administration of 0.9% NaCl solution (control) or medetomidine (10 or 20 micrograms/kg of body weight).

Results: Mean serum insulin concentration decreased after medetomidine administration and was significantly (P < or = 0.05) lower than control values 20, 40, 60, and 120 minutes after drug administration. Mean plasma glucose concentration tended to increase after medetomidine administration, but did not differ significantly from control values.

Conclusions: In dogs, i.v. administration of medetomidine at dosages of 10 and 20 micrograms/kg transiently decreases serum insulin concentration, but plasma glucose concentration remains within the normal physiologic range.

Clinical Relevance: Medetomidine can be given at low, preanesthetic dosages without significantly altering plasma glucose concentration in clinically normal dogs.