Effect of rioprostil, an oral prostaglandin E1 analogue, on lower oesophageal sphincter pressure and on the motility of the distal oesophagus in healthy volunteers.

The influence of rioprostil on the resting pressure of the lower oesophageal sphincter (LESP) and on the bolus-stimulated contraction wave amplitude of primary peristalsis is investigated in 9 healthy male volunteers receiving placebo or 300 micrograms and 600 micrograms of rioprostil orally in a randomized, double-blind, threefold crossover study. Manometry is performed using the low-compliance pneumohydraulic infusion system. The results show that: rioprostil, 600 micrograms, slightly increases LESP (ns) and contraction wave amplitudes, measured 10 cm above the lower oesophageal sphincter (LES) (p = 0.0039); rioprostil in both doses does not change the contraction wave amplitudes of the distal oesophagus, 5 cm above the LES; the duration of the peristaltic contractions is not altered. We conclude that rioprostil, in doses which effectively inhibit gastric acid and pepsin secretion and heal peptic ulcers, has no inhibitory effects on oesophageal motility. Studies are warranted, therefore, to establish the efficacy of rioprostil in the treatment of reflux oesophagitis.