Although the immediate success of endoscopic balloon dilation of nonmalignant and noncongenital pyloric stenosis is known, little information is available on the long-term results of such therapy. Of 19 patients who underwent this treatment at our institution for gastric outlet obstruction, 3 (16%) experienced sustained relief and 16 (84%) had a recurrence of symptoms during a median follow-up period of 45 months. Twelve of the patients who had a recurrence of gastric outlet obstructive symptoms required further therapy. Our results suggest that if followed for a prolonged period of time, patients who have undergone endoscopic balloon dilation of nonmalignant pyloric stenosis have a high recurrence rate of symptomatic gastric outlet obstruction.