A device for treating acid reflux comprising a sleeve configured and dimensioned for insertion into the esophagus of the patient, the sleeve having a proximal portion, a distal portion and an intermediate portion between the distal and proximal portions. The sleeve includes a an inner member applying a radial force on the sleeve for securement within the esophagus, and a skirt connected to the sleeve to block acid backup from the stomach while not inhibiting passage of food into the stomach.