The role of
cyclo-oxygenase 2 (COX-2) and
prostaglandins (PG) in
carcinogenesis has been documented in many species.
Piroxicam has shown efficacy against several
neoplasms and is frequently prescribed for chronic use. There are no studies investigating chronic
piroxicam administration in cats and the chronic use of
non-steroidal anti-inflammatory agents in this species has long been cautioned against. This retrospective study aimed to evaluate adverse effects in cats receiving long-term daily
piroxicam. Seventy-three cats received daily
piroxicam at doses of 0.13-0.41mg/kg.
Treatment duration ranged from 1 to 38 months. Treatment with
piroxicam was found to significantly increase frequency of
vomiting during the first month of
therapy, though this was most significant for cats receiving concurrent
chemotherapy.
Piroxicam administration was not significantly associated with hematologic, renal or hepatic toxicities. Adverse events were not correlated with dosage. Adverse events were reported in 29% of cats, and were generally mild and transient. Eight percent discontinued
piroxicam due to adverse reaction, and 4% due to difficult administration. This study indicates that long-term daily
piroxicam is generally well tolerated in cats at conventional doses.