Treatment of functional dyspepsia and gastroparesis

Functional dyspepsia (FD) and gastroparesis (GP) are the two most prevalent gastric neuromuscular disorders. These disorders are frequently confused, have more similarities than differences, and can be thought of as two ends of a continuous spectrum of gastric neuromuscular disorders (Fig. 1). FD is currently defined by the Rome III criteria; it is now subdivided into a pain-predominant subtype (epigastric pain syndrome) and a meal-associated subtype (post-prandial distress syndrome). GP is defined by symptoms in conjunction with delayed gastric emptying in the absence of mechanical obstruction. Symptoms for both FD and GP are similar and include epigastric pain or discomfort, early satiety, bloating, and post-prandial nausea. Vomiting can occur with either diagnosis; it is typically more common in GP. A patient suspected of having either FD or GP should undergo upper endoscopy. In suspected FD, upper endoscopy is required to exclude an alternative organic cause for the patient's symptoms; however, most (70 %) patients with dyspeptic symptoms will have FD rather than an organic disorder. In suspected GP, upper endoscopy is required to rule out a mechanical obstruction. A 4-hour solid-phase gastric emptying scan is recommended to confirm the diagnosis of GP; its utility is unclear in patients with FD, as it may not change treatment. Once the diagnosis of FD or GP is made, treatment should focus on the predominant symptom. This is especially true in patients with GP, as accelerating gastric emptying with the use of prokinetics may not necessarily translate into an improvement in symptoms. Unfortunately, no medication is currently approved for the treatment of FD and, thus, technically, all treatment options remain off-label, including medications for visceral pain (e.g., tricyclic antidepressants) and nausea. This review focuses on treatment options for FD and GP with an emphasis on new advances in the field over the last several years.