Abstract
The effect of a new tranquillizer, mepiprazole, in the treatment of the irritable bowel syndrome has been studied in a double-blind cross-over trial in 19 patients. After examination to exclude organic disease the patients were followed up over two treatment periods of four weeks each under either placebo or the active principle, each patient being his own control. The results indicated that the drug had a beneficial effect (P < 0·05) provided that it was given for a period of at least three weeks.