What medications help with gastro paresis (gastroparesis)?

Medications for Gastroparesis Management

Metoclopramide is the first-line prokinetic medication for gastroparesis, administered at 10 mg orally 30 minutes before meals and at bedtime, with use limited to 12 weeks due to risk of tardive dyskinesia. 1, 2

Pharmacological Treatment Options

First-Line Prokinetic Agents

• Metoclopramide

  • Dosing: 10 mg orally 30 minutes before meals and at bedtime
  • FDA-approved specifically for diabetic gastroparesis
  • Mechanism: Dopamine antagonist with prokinetic effects
  • Limitation: Use restricted to 12 weeks due to risk of tardive dyskinesia
  • For severe cases: Can be administered intravenously (10 mg slowly over 1-2 minutes) 2

• Erythromycin

  • Dosing: 40-250 mg orally three times daily
  • Alternative first-line agent
  • Limitation: Effectiveness diminishes over time due to tachyphylaxis 1

• Domperidone (not FDA-approved in US)

  • Dosing: 10 mg three times daily
  • Advantage: Does not readily cross blood-brain barrier, resulting in fewer central side effects
  • Limitation: Requires cardiac monitoring due to QT prolongation risk 1

Antiemetic Medications for Symptom Control

1. Phenothiazines (prochlorperazine, trimethobenzamide, promethazine)

   • Mechanism: Central antidopaminergic action in the area postrema 3
   • Use: As needed for nausea and vomiting

2. Serotonin (5-HT3) receptor antagonists (ondansetron, granisetron)

   • Mechanism: Block serotonin receptors in chemoreceptor trigger zone and inhibit vagal afferents
   • Use: As needed for nausea and vomiting, particularly effective for chemotherapy-induced symptoms 3, 1

3. NK-1 receptor antagonists (aprepitant)

   • Mechanism: Block substance P in areas involved in nausea and vomiting
   • Evidence: Clinical trials show improvement in nausea and vomiting using the Gastroparesis Cardinal Symptom Index 1

4. Other antiemetic options:

   • Tricyclic antidepressants
   • SNRIs
   • Anticonvulsants 1

Treatment Algorithm Based on Severity

Mild to Moderate Gastroparesis

1. Dietary modifications (cornerstone of management)

   • Low-fiber, low-fat diet
   • Small, frequent meals (5-6 per day)
   • Increased proportion of liquid calories
   • Foods with small particle size 3, 1

2. First-line medication:

   • Metoclopramide 10 mg before meals and at bedtime
   • Monitor for extrapyramidal side effects

3. If inadequate response or intolerance:

   • Switch to erythromycin
   • Add antiemetic agent as needed for symptom control

Severe or Refractory Gastroparesis

1. Combination therapy:

   • Consider combining prokinetic agents
   • Add appropriate antiemetic medication

2. Alternative approaches:

   • Somatostatin analogue (octreotide) - may be beneficial, especially in systemic sclerosis 1
   • Botulinum toxin injection into the pylorus - may provide modest temporary symptom improvement 3, 1

3. Nutritional support:

   • Transition from solid food to blended/pureed foods
   • Liquid diet with oral nutritional supplements
   • Consider enteral nutrition via jejunostomy tube for severe cases 1

4. Surgical interventions:

   • Gastric electrical stimulation (GES) - FDA-approved for treating refractory gastroparesis
   • Gastric peroral endoscopic myotomy (G-POEM) - for patients with severe delay in gastric emptying 1

Special Considerations

Drug-Drug Interactions

• Many medications used for gastroparesis are metabolized via common drug metabolizing enzymes, which can trigger potential drug-drug interactions 4
• Be cautious when combining prokinetics with antiemetics, antidiabetic agents, or other medications

Diabetic Gastroparesis

• Optimize glycemic control to prevent progression of gastroparesis
• Adjust insulin timing and dosage to account for delayed gastric emptying
• Consider DPP-4 inhibitors which have a neutral effect on gastric emptying 1

Geriatric Patients

• Use the lowest effective dose of metoclopramide
• Higher risk of developing parkinsonian-like side effects
• If parkinsonian symptoms develop, discontinue metoclopramide before initiating anti-parkinsonian agents 2

Important Cautions

• Metoclopramide carries a black box warning for tardive dyskinesia risk with long-term use (>12 weeks)
• Monitor for extrapyramidal symptoms, especially in younger patients and the elderly
• Erythromycin may contribute to antibiotic resistance with prolonged use
• Domperidone requires cardiac monitoring due to QT prolongation risk
• The correlation between gastroparesis symptoms and rates of gastric emptying is often poor 5

By following this structured approach to medication management for gastroparesis, symptoms can be effectively controlled while minimizing adverse effects and complications.