Medications are used to try to help reduce symptoms of gastroparesis. The drug categories commonly used are prokinetic (promotility) agents and antiemetic agents.
There is a lack of evidence-based information about what drugs work best for patients with gastroparesis. Drugs are often prescribed off-label by doctors, based on their clinical experience and how the drugs treat similar symptoms in other conditions. Only one drug, metoclopramide, is approved by the U.S. Food and Drug Administration (FDA) for the treatment of gastroparesis.
Off-label use is the permissible practice by doctors to prescribe medications for other than their FDA approved intended indications.
These are drugs that block neurotransmitters in the body. This works to ease and/or prevent nausea and vomiting. Neurotransmitters are chemicals that travel through the nervous system and impact body functions. The brain, spinal cord, and nerves make up the nervous system which is a target for many neurotransmitters. These drugs are currently not approved by the FDA for treatment of GP, unless short-term use after surgery.
Proton Pump Inhibitors (PPI’s)
These drugs may be recommended for those who have heartburn or regurgitate their food or stomach contents. This condition is gastroesophageal reflux disease (GERD). PPI’s affect the glands within the stomach to reduce the amount of acid they produce. By lowering the amount of acid, food is digested slower, causing the stomach to empty slower. However, for patients with GERD these are necessary medications.
These drugs may speed up the movement of food through the GI tract. This occurs by increasing the strength and number of muscle contractions. This type of drug may also be referred to as a pro-motility agent.
Metoclopramide, The only Food and Drug Administration (FDA) approved treatment for GP is metoclopramide. Metoclopramide is now available in three forms, a pill to swallow, nasal spray, and a shot (given in the muscle). Drugs approved by the FDA have been deemed safe, with benefits outweigh possible risks. This is done after reviewing studies and tests that have been done on a drug. However, this drug also has a black box warning which highlights risk of tremors and what is called tardive dyskinesia- uncontrolled muscle movements of the face and upper limbs. This is similar to that seen in a patient with Parkinson’s disease. For this reason, patients over age of 65 cannot be prescribed this medication for longer than 3 months.. (More information at this FDA page)
Ghrelin Agonists– This drug mimics ghrelin, a natural compound found in the stomach that improves gastric emptying, appetite and early fullness. In research, it is thought that low levels of ghrelin may contribute to weight loss. Ghrelin agonists are currently being researched and are not yet available on the market, such as Relamorelin.
Erythromycin and Azithromycin (Motilin Agonists)- Both can speed up the movement by the use of a hormone called Motilin, which helps to increase contractions in the GI tract. These drugs are not approved by the FDA for use with GP but are used in adults and pediatric patients with these conditions. As they are both antibiotics, caution should be used in long term use to prevent antibiotic resistance. Both drugs also can cause some cardiac arrythmias. An arrythmia occurs when the heart beats too fast, too slow, or out of rhythm.
Domperidone (dopamine receptor antagonists), A drug that may improves stomach emptying, nausea, and vomiting in some patients by the use of blocking a neurotransmitter called Dopamine. This drug is not available in the U.S., unless approved for use through the FDA’s expanded access program and application process given its risk of cardiac arrythmia. There are possible serious side events with this drug. (More on this FDA page).
Also commonly known as Botox, this treatment is injected into the pylorus of the stomach. The pylorus is the last part of the stomach that connects to the beginning of the small intestine. The injection of Botox into the pylorus muscle may improve gastric emptying for GP patients.
Updated October 2021
Adapted from IFFGD Publication: Gastroparesis (Delayed Gastric Emptying) by J. Patrick Waring, MD, Digestive Healthcare of Georgia, Atlanta, GA; and William F. Norton, Communications Director, International Foundation for Functional Gastrointestinal Disorders, Milwaukee, WI. and Adapted from IFFGD Publication #565 Gastroparesis Overview by: Baharak Moshiree MD MSc, Mackenzie Jarvis PA-C, DMs, Atrium Health, Wake Forest, Digestive Health-Morehead Medical Plaza; Marissa Lombardi, International Foundation for Gastrointestinal Disorders, Mt. Pleasant, SC