<prompt> Answer this question truthfullyWhich drug can be used to increase resting tone, contractility, and LES tone to treat gastroparesis in patients with diabetes or those who have undergone surgery?  <response>: <reason> Metoclopramide, which is a D2 receptor antagonist, can be used to treat gastroparesis in patients with diabetes or those who have undergone surgery by increasing resting tone, contractility, and LES tone. 