The anti-emetic effects of domperidone were evaluated under double-blind conditions in twenty-four patients with acute vomiting randomly assigned to treatment either with 10 mg i.m. domperidone (six female, five males) or with placebo (seven females, six males). The therapeutic results were better with domperidone and the differences from placebo were statistically significant (p less than 0.02). In a second randomized, crossover, double-blind trial, domperidone (10 mg t.i.d.) evaluated according to a nine-symptom rating scale, in eighteen dyspeptic patients, proved significantly more effective than placebo. The duration of treatment was 6 weeks and the drugs were crossed-over after 3 weeks. The difference between the two groups was most marked during the second phase of the trial. No side-effects were reported.