Effect of phenylbutazone on insulin secretion in horses with insulin dysregulation

Abstract

Background: Phenylbutazone is often prescribed to manage pain caused by hyperinsulinemia-associated laminitis, but in diabetic people nonsteroidal anti-inflammatory drugs increase insulin secretion and pancreatic activity. Hypothesis/Objectives: Investigate the effect of phenylbutazone administration on insulin secretion in horses. It was hypothesized that phenylbutazone will increase insulin secretion in horses with insulin dysregulation (ID). Animals: Sixteen light breed horses, including 7 with ID. Methods: Randomized cross-over study design. Horses underwent an oral glucose test (OGT) after 9 days of treatment with phenylbutazone (4.4 mg/kg IV q24h) or placebo (5 mL 0.9% saline). After a 10-day washout period, horses received the alternative treatment, and a second OGT was performed. Insulin and glucose responses were compared between groups (ID or controls) and treatments using paired t test and analyses of variance with P