Three children (ages 5, 7.6, and 8 years), with recurrent unexplained upper abdominal symptoms such as vomiting, epigastric pain, anorexia, early satiety and without structural or mucosal abnormalities of gastrointestinal tract, underwent electrogastrography (EGG)--recording of gastric electrical activity using cutaneous electrodes positioned on the epigastric region and connected to a recording polygraph. Frequency of EGG signals was analyzed by fast Fourier transform. Significant changes of fasting and fed gastric myoelectrical activity (tachygastria, bradygastria, flatline pattern) were recorded in the three patients; furthermore, gastric emptying (GE) of a solid-liquid mixed meal, measured by ultrasonography, was significantly prolonged in them. A follow-up study was carried out after an eight-week course with oral cisapride: in all patients symptoms improved, GE time normalized, and EGG analysis showed normal electrical rhythm. It is suggested that gastric dysrhythmias can play a pathogenetic role in patients with functional gastrointestinal symptoms and that symptomatic improvement is accompanied by normalization of gastric electrical rhythm.