What are the American Gastroenterological Association (AGA) guidelines for the management of gastroparesis?

American Gastroenterological Association Guidelines for Management of Gastroparesis

The American Gastroenterological Association recommends primary treatment of gastroparesis through dietary modifications, antiemetic agents, and prokinetic medications, with metoclopramide being the only FDA-approved medication for this condition. 1

Diagnosis and Evaluation

• Gastroparesis is diagnosed based on the presence of clinical symptoms (nausea, vomiting, early satiety, postprandial fullness, bloating, upper abdominal pain) and documentation of delayed gastric emptying in the absence of mechanical obstruction. 1
• Gastric emptying scintigraphy of a radiolabeled solid meal is the best accepted method to test for delayed gastric emptying, with a 4-hour test duration recommended to increase diagnostic yield. 1
• Antroduodenal manometry may help differentiate between neuropathic or myopathic motility disorders and can diagnose unexpected small bowel obstruction or rumination syndrome. 1

First-Line Treatment Approach

Dietary Modifications

• Eat frequent smaller-sized meals and replace solid food with liquids (such as soups). 1
• Foods should be low in fat and fiber content. 1
• For patients with mild symptoms, dietary modifications may provide satisfactory symptom control. 2

Pharmacological Management

Prokinetic Agents

• Metoclopramide is the first-line prokinetic agent and only FDA-approved medication for gastroparesis. 1, 3
  • Standard dosing: 10 mg three times daily before meals for at least 4 weeks. 1
  • For severe symptoms, therapy may begin with metoclopramide injection (IM or IV). 3
  • Clinicians should be aware of the black box warning for tardive dyskinesia, although risk may be lower than previously estimated. 1
  • For patients with renal impairment (creatinine clearance below 40 mL/min), initiate at approximately half the recommended dosage. 3

Antiemetic Agents

• Antiemetic agents are administered for nausea and vomiting. 1
• Principal classes include:
  • Antidopaminergics (prochlorperazine, trimethobenzamide, promethazine) 1
  • Antihistamines 1
  • Anticholinergics 1
  • Serotonin (5-HT3) receptor antagonists - best used on an as-needed basis 1

Management of Refractory Gastroparesis

Medically refractory gastroparesis is defined as persistent symptoms despite dietary adjustment and metoclopramide therapy. 1

Approach Based on Predominant Symptoms

• Treatment should be tailored based on the predominant symptom (nausea/vomiting vs. abdominal pain/discomfort) and symptom severity. 1

• For nausea/vomiting predominant symptoms:

  • Mild: Anti-emetic agents 1
  • Moderate: Combination of anti-emetic and prokinetic agents, cognitive behavioral therapy/hypnotherapy, liquid diet 1
  • Severe: Consider enteral feeding (J tube) or gastric electrical stimulation 1

• For abdominal pain/discomfort predominant symptoms:

  • Treat similar to functional dyspepsia 1
  • Consider augmentation therapy for moderate symptoms 1
  • Address comorbid affective disorders 1

Alternative Prokinetic Agents

• Erythromycin - can be administered orally or intravenously 1
• Domperidone - a dopamine (D2) receptor antagonist (not FDA-approved in the United States but available in Canada, Mexico, and Europe) 1

Advanced Interventions for Refractory Cases

• Gastric electrical stimulation (GES) - approved on a humanitarian device exemption basis

  • High-frequency gastric electric stimulation has shown improvement in symptoms with modest changes in gastric emptying 1
  • Most beneficial for patients with diabetic gastroparesis 4
  • Can reduce weekly vomiting frequency and need for nutritional supplementation 2

• Endoscopic and surgical options:

  • Decompressing gastrostomy and feeding jejunostomy tubes for patients unable to maintain adequate nutrition 1, 2
  • Intrapyloric botulinum toxin injection is not recommended based on placebo-controlled studies showing no benefit 1
  • Gastric per-oral endoscopic myotomy (G-POEM) should only be performed at tertiary care centers by experts in treating refractory gastroparesis 1

Special Considerations

• For diabetic gastroparesis, careful regulation of glycemic control may help reduce symptoms 4
• Partial gastrectomy and pyloroplasty should be used rarely and only in carefully selected patients 2
• Parenteral nutrition should be used only briefly during hospitalization and not encouraged as an outpatient treatment 5

Treatment Algorithm for Gastroparesis

1. Confirm diagnosis with gastric emptying study
2. Implement dietary modifications (small, frequent, low-fat, low-fiber meals)
3. Start metoclopramide (if no contraindications) and appropriate antiemetics
4. For diabetic patients, optimize glycemic control
5. If symptoms persist after 4 weeks of optimal therapy, consider:
   • Alternative or combination prokinetic agents
   • Intensified antiemetic therapy
   • Nutritional support if needed
6. For truly refractory cases, consider referral to a tertiary center for:
   • Gastric electrical stimulation
   • Enteral feeding via jejunostomy
   • Consideration of emerging endoscopic therapies