Pharmacokinetics and suggested oral dosing regimen of cisapride: a study in healthy cats.

The disposition of cisapride in seven healthy cats was determined following administration of either a single oral (2 mg/kg body weight) or intravenous (i.v.) (1 mg/kg body weight) dose. Cats were studied using a random crossover design. After administration of the oral capsule, maximum plasma drug concentration (Cmax) +/- standard deviation (SD) was 73.32 +/- 16.59 ng/ml, and bioavailability +/- SD was 29.0 +/- 22.6%. Following i.v. administration, extrapolated peak cisapride concentration (C0) +/- SD was 421.30 +/- 155.37 ng/ml, and clearance +/- SD was 15 +/- 0.67 ml/kg per minute. Elimination half-life (T1/2) was similar for both routes of administration (T1/2(oral) +/- SD was 5.27 +/- 3.16 hr, T1/2(i.v.) +/- SD was 5.19 +/- 3.77 hr). Adverse effects were not observed. Based on these results, a dose of 1 mg/kg body weight per os (PO) every eight hours or 1.5 mg/kg body weight every 12 hours is expected to result in plasma drug concentrations within the therapeutic ranges established for humans.