Migration of the adjustable gastric band (AGB) is a serious complication which usually does not require emergency treatment, except when there is a risk to life. We report a 30-year-old patient who presented with syncope, melena and hypovolemic shock due to the intragastric erosion of an AGB, 13 months after laparoscopic band placement. The diagnosis of migration had been made 7 months after placement, and bleeding only occurred 6 months later. Greater intraluminal penetration had been awaited to facilitate gastroscopic extraction, but, faced with hemodynamic instability, resuscitation was carried out followed by emergency endoscopy to cut the device, using endoscopic scissors. Then, the band was removed orally. There has been no recurrence of hemorrhage 12 months later. Delayed treatment may be indicated in cases of initial band migration; however, rigorous follow-up is necessary with frequent re-evaluation, to diagnose potentially life-threatening complications promptly.