What are the first-line medications for treating gastroparesis?

First-Line Medications for Gastroparesis

Metoclopramide is the only FDA-approved medication for the treatment of gastroparesis and should be considered first-line pharmacologic therapy for severe cases, though its use should be limited to 12 weeks due to risk of serious adverse effects. 1, 2

Non-Pharmacologic Management (First Steps)

Before initiating medications, dietary modifications should be attempted:

• Consume frequent smaller meals with a greater proportion of liquid calories 2
• Follow a low-fiber, low-fat diet 2
• Choose foods with small particle size to improve key symptoms 1, 2
• Consider liquid nutritional supplements if needed for adequate nutrition 2

Pharmacologic Management

First-Line Medication Options:

• Metoclopramide:
  • Only FDA-approved medication for gastroparesis in the United States 1, 2
  • Typical dosage: 10 mg three times daily before meals 2
  • Available in oral or intravenous formulations 2
  • Important caution: Use should be limited to 12 weeks due to risk of serious adverse effects including extrapyramidal symptoms (acute dystonic reactions, drug-induced parkinsonism, akathisia) and tardive dyskinesia 1
  • Should be reserved for severe cases unresponsive to dietary modifications 1

Alternative Medication Options:

• Erythromycin:

  • Effective for short-term use only due to tachyphylaxis (diminishing response with continued use) 1, 2
  • Acts as a motilin receptor agonist to stimulate gastric motility 3

• Domperidone:

  • Not FDA-approved in the US but available through FDA's Expanded Access to Investigational Drugs program 1, 3
  • Available outside the United States 1
  • Has fewer central nervous system side effects than metoclopramide 4

Management Algorithm

1. Start with dietary modifications and lifestyle changes
2. Withdraw medications that may worsen gastroparesis (opioids, anticholinergics, tricyclic antidepressants, GLP-1 receptor agonists, pramlintide) 1, 2
3. For patients with severe symptoms unresponsive to dietary changes:
   • Initiate metoclopramide (limit to 12 weeks) 1, 2
   • Consider erythromycin for short-term use 1, 2
   • For patients in the US with intolerance to metoclopramide, consider domperidone through expanded access 3

Special Considerations

• Diabetic gastroparesis: Careful glycemic control is essential as hyperglycemia can worsen gastric emptying 2
• Monitoring: Regular assessment for extrapyramidal symptoms is crucial when using metoclopramide 1
• Refractory cases: Consider enteral nutrition via jejunostomy tube for patients with persistent vomiting or weight loss 2, 4
• Gastric electrical stimulation: FDA-approved but has limited data supporting efficacy in diabetic gastroparesis 1

Common Pitfalls

• Continuing metoclopramide beyond 12 weeks without careful monitoring for neurological side effects 1, 2
• Failing to withdraw medications that may worsen gastroparesis symptoms 1
• Relying solely on pharmacologic therapy without implementing dietary modifications 2
• Expecting complete symptom resolution with current available therapies, as most treatments provide only partial relief 4