PHARMACOKINETICS AND TOLERANCE OF AN ORAL LY-ADMINISTERED COMBINATIONOF PHENYLBUTAZONE AND PREDNISOLON IN DOGS

Tolerance and pharmacokinetics of a combination of phenylbutazone and prednisolone (tablets) were studied in Beagle dogs. For two weeks, the drug was administered orally (3.33 mg/kg phenylbutazone combined with 0.1 mg/kg prednisolone and 6.66 mg/kg phenylbutazone combined with 0. 3 mg/kg prednisolone twice daily). The dosage was reduced to 50 per ce nt after one week. No signs of intolerance were found. After treatment with 3.33 mg/kg phenylbutazone, a plasma concentration of 10 mu g/ml was reached within 1 to 2 hours. No prednisolone concentration above 2 ng/kg was measured. Additionally, a synergistic antiinflammatory effe ct of the two ingredients was obvious (hind paw dextran edema in rats) . In addition to results of ENGELKE et al. (1995) who studied the clin ical efficacy of the combination, the presented data demonstrate a goo d tolerance.