Study of the bioavailability of pindolol in malabsorption syndromes

Pindolol kinetics and bioavailability were studied after a single dose (oral 5 mg; intravenous 3 mg) in nine patients with malabsorption (two with villous atrophies, seven with short bowel syndromes) and in six healthy volunteers. After oral administration no significant differences were observed in bioavailability (59.4 +/- 6.2% in patients vs 79.5 +/- 8.6% in controls) and for most plasma and urinary pharmacokinetic parameters between the experimental and control groups as a whole. However, detailed analysis revealed decreased absorption for pindolol in two out of nine patients. After i.v. administration, apparent distribution volume was smaller (V: 2.10 +/- 0.25 l kg-1 vs 3.05 +/- 0.31 l kg-1) and global elimination constant was larger (ke: 1.43 +/- 0.46 h-1 vs 0.56 +/- 0.10 h-1), in patients with malabsorption than in controls (P less than 0.05). The smaller weight of patients and pharmacokinetic modifications due to the pathology could account for this.