Postoperative pharmacokinetics of meloxicam in horses after surgery for colic syndrome

NSAIDs are often used in horses with colic syndrome during the postoperative period, due to their ability to contrast endotoxemia and to promote an analgesic and anti-inflammatory effect. As the pharmacokinetics of a drug are often modified in unhealthy animals compared to healthy subjects, the aim of this study was to evaluate the pharmacokinetic profile of meloxicam after i.v. administration in horses undergoing laparotomy for colic syndrome. Eight horses received 0.6 mg/kg of meloxicam i.v. towards the end of surgery. Blood samples were taken at scheduled time points during the following 24 hr. The serum concentration of the drug was determined by HPLC. Terminal half-life (6.88 ± 2.96 hr), volume of distribution at steady-state (186.53 ± 61.20 ml/Kg) and clearance (27.91 ± 5.72 ml kg-1 hr-1 ) were similar to those reported in literature for healthy horses. This result suggests that no adjustment of the approved dose should be necessary when meloxicam is used to treat horses in the immediate postoperative period after surgery for colic syndrome.