Ninety patients undergoing Tc-99m disofenin hepatobiliary scintigraphy for suspected acute cholecystitis were assessed for enterogastric reflux. Seventy-seven cases showed bowel activity by one hour and were included in the study. Twenty-six percent (20/77) showed definite enterogastric reflux. The gastric activity tended to clear rapidly, even though patients remained supine during examination. Six of 20 patients (30%) with enterogastric reflux had gallbladder visualization. Of these six, one had acute cholecystitis and one had resolving acute cholecystitis with gallstone pancreatitis. There was one case each of pancreatitis, amebic abscess, sepsis, and one normal. Thus, of 20 patients with enterogastric reflux, 16 had acute cholecystitis (80%). Twenty-three of seventy-seven patients (30%) had surgically proven acute cholecystitis: of these, 16 of 23 (70% sensitivity) had gastric reflux, and 50 of 54 without acute cholecystitis did not have reflux (93% specificity). The overall accuracy of enterogastric reflux for acute cholecystitis is 86%. Gastric reflux seen on cholescintigraphy is a secondary sign of acute cholecystitis. Reflux may be related to duodenal irritation from the adjacent inflamed gallbladder.