PHARMACOKINETICS OF SINGLE DOSE ORAL MELOXICAM IN BOTTLENOSE DOLPHINS (TURSIOPS TRUNCATUS)

Abstract

The objective of this study was to investigate the pharmacokinetics of meloxicam in bottlenose dolphins (Tursiops truncatus). Ten adult bottlenose dolphins were used for the study. Each animal received a single oral dose of meloxicam at 0.1 mg/kg. Two to seven serial blood samples were collected per animal, at one of fourteen time points between T = 0 and T = 240 hr. Complete blood count and serum chemistry analysis were performed prior to drug administration, as well as at the final time point for each individual. Plasma drug concentrations were determined by high-pressure liquid chromatography. No adverse hematological, biochemical or clinical changes were noted during the study period. After oral administration, a peak plasma concentration of 1.03 microg/mL was achieved at approximately 11 hr. This suggests that a single oral dose of 0.1 mg/kg provides a peak plasma level similar to what is considered therapeutic in other species. However, the elimination of meloxicam in cetaceans was slower than in other species, with an elimination half-life of almost 70 hr, and detectable drug concentrations up to 7 days. A single oral dose of 0.1 mg/kg appears safe for use in this species, but caution in repeated dosing must be used, due to the prolonged elimination, until multi-dose pharmacokinetic studies are determined.

Piroxicam and doxycycline treatment for an oral squamous cell carcinoma in an inshore bottlenose dolphin (Tursiops aduncus)

“…In contrast, the animal in this case had a total treatment period of 14 days and a partial remission in excess of 2400 days. The reason for this is unclear and while it is assumed that cetaceans have a system of cyclooxygenases similar to mammals, the role of specific mediators in the inflammatory cascades are yet to be defined and are worthy of further research.…”

“…However, piroxicam, as a non‐selective COX inhibitor, also inhibits the COX1 enzymes that are responsible for the maintenance of normal cellular function, which can lead to renal toxicity and gastric ulceration and although various NSAIDs have been administered to cetaceans, these animals appear to be particularly sensitive to the associated side effects, particularly gastrointestinal ulceration . A recent pharmacokinetic study showed that the elimination half‐life of meloxicam in bottlenose dolphins ( Tursiops truncatus ) was significantly longer than in other species and hence caution is required with its long‐term use. The use of piroxicam in bottlenose dolphins has not been documented and poses an additional risk given the non‐selective nature of this NSAID.…”