Pharmacokinetics of sulfamethoxypyridazine following intravenous administration in renal impaired goats

Pharmacokinetics of sulfamethoxypyridazine (SMPZ) was studied following int ravenous dose (25mg/kg) in normal and renal impaired goats. Therapeutic con centration (25 mu g/ml) in plasma was maintained upto 4 and 18h in normal a nd renal impaired goats, respectively. The plasma elimination half life was 29h, 36 min in renal impaired goats compared to 6h, 5min in normal ones. t he volume of distribution was similar in both normal and renal impaired goa ts. Clearance of SMPZ was significantly (p < 0.01) lower in renal impaired goats (0.25ml/min/kg) compared to normal ones (1ml/min/kg). Area under the curve was significantly (P<0.01) higher in renal impaired (100196 mu g/ml.m in) compared to normal goats (24876 mu g/ml.min). Based on the pharmacokine tic parameters intravenous dosage regimen in renal impaired goats (priming dose of 27.5mg/kg followed by maintenance dose of 13mg/kg at 24h interval) and goats with normal kidneys (priming dose of 33.5mg/kg followed by mainte nance dose of 20mg/kg at 8h interval) is recommended.