Nonsteroidal anti-inflammatory drugs (NSAIDs) are a class of analgesics commonly used for the treatment of pain associated with inflammation in both human and veterinary medicine.1 Meloxicam is a drug product formulated for single-use, subcutaneous injection at a dose of 0.3 mg/kg for the control of postoperative pain and inflammation associated with orthopedic surgery, ovariohysterectomy and castration in domestic felids. The most common indications for use of meloxicam in nondomestic felids include acute (postoperative), and chronic (degenerative osteoarthritis) pain. While NSAIDs are a common treatment option, information regarding their safety, efficacy, and adverse event profiles in nondomestic felids remains limited.3,4 This study represents the first use of population pharmacokinetics (PPK) and sparse data collection to report pharmacokinetic parameters in nondomestic felids. The purpose of this study was to compare and contrast PPK profiles between lions (Panthera leo; n=22), cheetahs (Acinonyx jubatus; n=9) and tigers (Panthera tigris; n=6). Each subject, at their respective zoological institute, received an oral dose of meloxicam (0.1–0.2 mg/kg) and up to three blood samples were voluntarily drawn at time points ranging from 2–4 h, 8–12 h, and 20–24 h. Serum drug concentrations were evaluated at each time point and an appropriate PPK model was established based on the Akaike information criterion (AIC) and -2 log likelihood (-2LL) score. In lions, the maximum serum concentration (Cmax) was 817.9 ng/ml, the corresponding time (Tmax) was 2.1 h, and a terminal half-life (t1/2) of 5.92 h. In cheetahs, Cmax was 1412.14 ng/ml, Tmax was 10.03 hr, with a terminal t1/2 of 8.11 h. Tiger Cmax was 613.7 ng/ml, Tmax was 2 h, with a terminal t1/2 of 6.31 h. Oral absorption rate in cheetahs appears to be much slower as compared to both lions and tigers, but all three species were able to achieve therapeutic serum drug concentrations based on the domestic felid pain model.2
Funding for this project was provided by the Morris Animal Foundation Grant ID: D15ZO-805. This project would not have been possible without the technical skill and organization from veterinarians and staff from all the facilities who contributed to the study. These facilities include Birmingham Zoo, Detroit Zoological Society, Lion Country Safari, White Oak Conservation Holdings, LLC, Jacksonville Zoo & Garden, Louisville Zoo, San Diego Zoo, North Carolina Zoo, Oregon Zoo, and the San Francisco Zoo.
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2. Lehr T, Narbe R, Jöns O, Kloft C, Staab A. Population pharmacokinetic modelling and simulation of single and multiple dose administration of meloxicam in cats. J Vet Pharmacol Ther. 2010;33:277–286.
3. Whiteside DP, Black SR. The use of meloxicam in exotic felids at the Calgary Zoo. Proc Am Assoc Zoo Vet, Am Assoc Wildl Vet, and Wildl Dis Assoc; 2004:342–345.
4. Whiteside DP, Remedios AM, Black SR, Finn-Bodner ST. Meloxicam and surgical denervation of the coxofemoral joint for the treatment of degenerative osteoarthritis in a Bengal tiger (Panthera tigris tigris). J Zoo Wildl Med. 2006;3:416–419.