GI stimulants 

Gastrointestinal stimulants are drugs that increase motility of the gastrointestinal smooth muscle, without acting as a purgative. These drugs have different mechanisms of action but they all work to move the contents of the gastrointestinal tract faster.

Gastrointestinal stimulants are used to treat gastroesophageal reflux disease and other gastrointestinal conditions where gastrointestinal movement is slowed.

Studies in animals and man have shown that metoclopramide, bethanechol and domperidone enhance the peristaltic contractions of the esophageal body, increase the muscle tone of the lower esophageal sphincter, and stimulate gastric motor activity.

These drugs mimic acetylcholine, a neurotransmitter that stimulates your intestinal muscles to contract. Examples include baclofen, bethanechol, neostigmine and pyridostigmine.

Examples of stimulants include: Amphetamines: Adderall® and Dexedrine®Caffeine. Cocaine.