What are the treatment options for a patient with gastroparesis?

Gastroparesis Medication Management

Start with dietary modifications (small particle size, low-fat diet for minimum 4 weeks) combined with metoclopramide 10 mg three times daily before meals and at bedtime for at least 4 weeks as first-line therapy, as this is the only FDA-approved medication for gastroparesis. 1, 2

Initial Treatment Approach

Dietary Modifications

• Implement small particle size, reduced fat diet for a minimum of 4 weeks before labeling treatment as failed 1
• Progress to liquid diet if solid food tolerance remains poor 1
• Frequent smaller meals with low fat and fiber content 1

First-Line Prokinetic Agent

• Metoclopramide is the only FDA-approved medication for gastroparesis and should be prescribed at 10 mg three times daily before meals and at bedtime for at least 4 weeks 1, 2
• Be aware of the black box warning for tardive dyskinesia, though the actual risk may be lower than previously estimated 1
• Limit use to 12 weeks maximum when possible due to extrapyramidal side effects 3
• Dosing can range from 5-20 mg three to four times daily depending on response 3

Symptom-Based Antiemetic Selection

• For nausea and vomiting as predominant symptoms, initiate antiemetic agents alongside prokinetics 1
• Phenothiazines (prochlorperazine 5-10 mg four times daily, promethazine, trimethobenzamide) work via central antidopaminergic mechanisms 1, 3
• 5-HT3 receptor antagonists (ondansetron, granisetron) are effective but should be used cautiously due to QTc prolongation risk 1, 3
• Use antiemetics on an as-needed basis rather than scheduled dosing 1

Medically Refractory Gastroparesis

When symptoms persist despite 4 weeks of dietary modification and metoclopramide, consider the patient medically refractory 1

Alternative Prokinetic Agents

• Prucalopride is recommended as first-line prokinetic for severe gastroparesis as it accelerates gastric emptying without cardiac effects, with RCT data showing improvement in both diabetic and idiopathic gastroparesis 3
• Erythromycin (oral or intravenous) can be used, primarily for short-term benefit 1
• Domperidone (10 mg TID or QID) is NOT FDA-approved in the United States but available in Canada, Mexico, and Europe; requires baseline ECG due to QTc prolongation risk at doses above 10 mg TID 3, 4

Advanced Antiemetic Options

• Aprepitant and tradipitant are highly effective for nausea and vomiting without cardiac concerns, with RCT data demonstrating improvement in gastroparesis patients 3
• Avoid ondansetron and granisetron in patients with cardiac risk factors due to QTc prolongation 3

Pain Management

• Amitriptyline 25-100 mg/day is the preferred neuromodulator for visceral pain in severe gastroparesis, as it does not prolong QTc interval and also helps with nausea 3
• Consider cognitive behavioral therapy and hypnotherapy for moderate symptoms 1

Severe Refractory Disease

Nutritional Support

• Enteral feeding via jejunostomy tube when oral intake is inadequate 1, 5
• Decompressing gastrostomy tubes occasionally necessary 1
• Parenteral nutrition rarely required 5

Procedural Interventions

• Gastric electrical stimulation (GES) is FDA-approved under Humanitarian Device Exemption for severe refractory gastroparesis, showing improvement in weekly vomiting frequency and nutritional supplementation needs 3, 5
• Gastric per-oral endoscopic myotomy (G-POEM) is an alternative option 1, 3
• Botulinum toxin injection into the pylorus showed modest temporary benefit in open-label trials but was not effective in randomized controlled trials 1, 5

Surgical Options (Last Resort)

• Partial gastrectomy and pyloroplasty should be used rarely, only in carefully selected patients 5

Critical Pitfalls to Avoid

• Do not use domperidone without baseline ECG and electrolyte assessment 4
• Do not exceed domperidone 10 mg TID due to increased QTc prolongation risk 3, 4
• Avoid domperidone in Parkinson's disease patients due to dopamine antagonism 4
• Rule out medication-induced gastroparesis (opioids, GLP-1 agonists) before escalating therapy 1
• Exclude gastroparesis mimics: cyclic vomiting syndrome, rumination syndrome, cannabinoid hyperemesis syndrome, functional dyspepsia, celiac artery compression syndrome 1
• Perform physical examination for succussion splash (delayed emptying/obstruction), right upper quadrant bruit (celiac compression), digital ulcers/telangiectasia (scleroderma), ascites/masses (malignancy) 1

Renal Impairment Dosing

• In patients with creatinine clearance below 40 mL/min, initiate metoclopramide at approximately one-half the recommended dosage and adjust based on efficacy and safety 2