What are the treatment options for gastroparesis?

Treatment of Gastroparesis

Begin with dietary modifications and medication withdrawal, followed by metoclopramide as first-line pharmacologic therapy, reserving erythromycin and domperidone for refractory cases, with gastric electrical stimulation as a last resort for severe symptoms unresponsive to all other treatments. 1, 2, 3

Initial Management: Non-Pharmacologic Interventions

Dietary Modifications

• Implement a low-fiber, low-fat eating plan with small frequent meals and a greater proportion of liquid calories 1
• Use foods with small particle size to improve key symptoms 1, 3
• Replace solid food with liquids such as soups 3

Medication Withdrawal

• Immediately discontinue medications that worsen gastrointestinal motility, including opioids, anticholinergics, tricyclic antidepressants, GLP-1 receptor agonists, and pramlintide 1, 2, 3
• Balance the risk of removing GLP-1 receptor agonists against their potential benefits, particularly in diabetic patients 1

Glycemic Control (Diabetic Patients)

• Optimize glycemic control in diabetic patients, as hyperglycemia directly worsens gastric emptying 2

First-Line Pharmacologic Therapy: Metoclopramide

FDA-Approved Treatment

• Metoclopramide is the only FDA-approved medication for gastroparesis and should be the first pharmacologic choice 1, 2, 3, 4
• Dose at 10 mg three times daily before meals 2, 4
• Administer for at least 4 weeks to assess efficacy 3

Critical Safety Limitations

• Limit use to 12 weeks maximum due to FDA black box warning for serious adverse effects, including extrapyramidal symptoms (acute dystonic reactions, drug-induced parkinsonism, akathisia) and tardive dyskinesia 1, 2, 3
• Reserve for severe cases unresponsive to other therapies when used beyond initial treatment period 1
• Use lower doses in geriatric patients, as the risk of parkinsonian-like side effects increases with age 4
• Adjust dosing in renal impairment: initiate at approximately half the recommended dose when creatinine clearance is below 40 mL/min 4

Acute Management

• For severe symptoms, begin with intravenous or intramuscular metoclopramide 4
• Administer 10 mg slowly IV over 1-2 minutes 4
• Continue IV administration up to 10 days until symptoms subside, then transition to oral therapy 4

Antiemetic Therapy

Symptom-Directed Treatment

• Administer antiemetic agents for nausea and vomiting as needed 3
• Principal classes include antidopaminergics (prochlorperazine, trimethobenzamide, promethazine), antihistamines, anticholinergics, and serotonin (5-HT3) receptor antagonists 3
• Use 5-HT3 receptor antagonists on an as-needed basis rather than scheduled dosing 3

Second-Line Pharmacologic Options

Erythromycin

• Reserve erythromycin for patients who fail or cannot tolerate metoclopramide 2
• Particularly useful in acute settings or when intravenous therapy is needed 2
• Major limitation: rapid development of tachyphylaxis makes it effective only for short-term use 1, 2
• Can be administered orally or intravenously 3

Domperidone

• Available outside the United States (Canada, Mexico, Europe) as an alternative dopamine D2 receptor antagonist 1, 3
• Not FDA-approved in the United States 3

Management of Refractory Gastroparesis

Definition and Assessment

• Medically refractory gastroparesis is defined as persistent symptoms despite dietary adjustment and metoclopramide therapy 3
• Tailor treatment based on predominant symptom (nausea/vomiting vs. abdominal pain/discomfort) and severity 3

Nausea/Vomiting Predominant Symptoms

• Mild: Antiemetic agents 3
• Moderate: Combination of antiemetic and prokinetic agents, cognitive behavioral therapy/hypnotherapy, liquid diet 3
• Severe: Consider enteral feeding via jejunostomy tube or gastric electrical stimulation 3

Abdominal Pain/Discomfort Predominant Symptoms

• Treat similar to functional dyspepsia 3
• Consider augmentation therapy for moderate symptoms 3
• Address comorbid affective disorders 3

Advanced Interventions

Enteral Nutrition

• Place jejunostomy tube for enteral feeding when oral intake is inadequate despite optimal medical therapy 3
• Parenteral nutrition is rarely required and only when hydration and nutritional state cannot be maintained 3

Gastric Electrical Stimulation (GES)

• FDA-approved for severe symptoms refractory to all other treatments 1, 3
• Efficacy is variable and use is limited to patients with severe symptoms unresponsive to other therapies 1
• Should only be performed at tertiary care centers by experts 3

Ineffective Interventions

• Intrapyloric botulinum toxin injection is not recommended based on placebo-controlled studies showing no benefit 3

Endoscopic and Surgical Options

• Gastric per-oral endoscopic myotomy (G-POEM) should only be performed at tertiary care centers by experts in treating refractory gastroparesis 3
• Partial gastrectomy and pyloroplasty should be used rarely, only in carefully selected patients with end-stage disease 3

Treatment Algorithm Summary

1. Confirm diagnosis with gastric emptying scintigraphy (4-hour test) 3
2. Implement dietary modifications (low-fiber, low-fat, small frequent meals, liquid calories) 1, 3
3. Withdraw offending medications (opioids, anticholinergics, GLP-1 RAs, etc.) 1, 2
4. Optimize glycemic control in diabetic patients 2
5. Start metoclopramide 10 mg three times daily before meals (if no contraindications) and appropriate antiemetics 2, 3, 4
6. Assess response after 4 weeks of optimal therapy 3
7. If symptoms persist: Consider alternative or combination prokinetic agents (erythromycin short-term) and intensified antiemetic therapy 2, 3
8. For truly refractory cases: Refer to tertiary center for gastric electrical stimulation, enteral feeding via jejunostomy, or consideration of emerging endoscopic therapies 3

Critical Pitfalls to Avoid

• Do not use metoclopramide beyond 12 weeks without careful reassessment of risks versus benefits due to tardive dyskinesia risk 1, 2
• Do not rely on erythromycin for long-term management due to inevitable tachyphylaxis 1, 2
• Do not perform intrapyloric botulinum toxin injection, as controlled trials demonstrate no benefit 3
• Do not proceed to gastrectomy or pyloroplasty without exhausting all medical and less invasive options at specialized centers 3
• In diabetic patients, do not overlook the impact of poor glycemic control on gastric emptying 2