Systemic use of pentosan polysulphate in the treatment of osteoarthritis.

Forty dogs diagnosed as having chronic osteoarthritis took part in a double-blind clinical dose-response study using the antiarthritic agent pentosan polysulphate (PPS). After complete physical examination to ensure good general health, dogs received four subcutaneous injections at intervals of one week 0, 1, 3 or 5 mg/kg PPS from code-numbered bottles. At weekly intervals and four weeks after the last injection, weakness, stiffness, pain on joint manipulation, willingness to exercise, body condition and overall response were scored. There were no differences between groups in baseline data, but dogs receiving PPS had a favourable response compared to dogs receiving a placebo for lameness, body condition, pain on joint manipulation and willingness to exercise. The 3 mg/kg dose rate gave the best improvement, the 1 mg/kg dose was partially effective and the 5 mg/kg group was least effective. The use of PPS at a dose rate of 3 mg/kg for the treatment of clinical osteoarthritis in dogs is indicated by our study.