Prokinetics are medications that stimulate contractions of the stomach muscles. Although these drugs may be used to treat dyspepsia, they are primarily used to prevent episodes of gastroesophageal reflux disease (GERD), in which acid from the stomach moves up into the esophagus, causing heartburn and damaging the tissue.

In healthy individuals, the lower esophageal sphincter (LES) – which is located at the junction of the stomach and the esophagus – keeps digestive acids in the stomach. However, this valve is weakened in some patients, which prevents it from closing tightly and allows acid to be refluxed back up into the esophagus. This can damage the tissue of the esophagus and cause the burning sensation in the chest known as heartburn.

Prokinetics reduce this abdominal discomfort by tightening the LES. This helps prevent acid from refluxing from the stomach into the esophagus. These medications also help the stomach to empty faster, which further reduces the reflux of stomach acid.  

For example, the prokinetic metoclopramide lowers the pressure threshold in the stomach that triggers the process of peristalsis (coordinated, rhythmic muscle contractions that help move food through the digestive tract). This drug also boosts both the strength and frequency of muscle contractions and relaxes the pyloric sphincter, which helps food in the stomach empty more quickly into the small intestine.

In addition to helping prevent or reduce reflux, metoclopramide is sometimes used to treat abdominal pain and gastroparesis (disorder in which the stomach takes too long to empty its contents) caused by diabetes. Metoclopramide acts on the brain to reduce nausea and vomiting and helps boost appetite.

Although prokinetics can be effective in treating certain disorders, they only provide short-term symptom relief for patients. In addition, they commonly cause side effects that somewhat limit their usefulness. For example, metoclopramide is associated with depression and severe muscle twitching. The medication bethanecol may cause dizziness or lightheadedness. The prokinetic cisapride has been linked to fatal heart arrhythmias (abnormalities in heartbeat rhythm) and is now only available to patients who meet certain criteria established by the drug’s manufacturer. A physician must enroll a patient in a special program before the medicine is provided.

Researchers continue to look at ways to improve prokinetics so they cause fewer side effects.

Prokinetics are available in tablet, oral solution and injection form. Certain prokinetics such as cisapride and domperidone are not available by prescription in the United States. Types of prokinetics include: