I. Clinical aspects
- Delayed gastric emptying, not related to diabetic nephropathy
- Nausea, esp. post-prandial
- Vomiting, esp. undigested food and bezoars
- Epigastric pain, bloating, early satiety, anorexia
- Unpredictable blood glucose fluctuations
- May be worse during periods of hyperglycemia, but relationship between duration/severity of DM and gastroparesis is not established
- Prevalence is about 33% of diabetics
II. Diagnosis: radionucleide test meal
III. Treatment
- Non-pharmacologic: avoid high-fat, high-fiber meals. Liquid, iso-osmotic meals have been used in severe cases.
- Prokinetic agents: work well, though poor correlation between symptoms and degree of impairment of gastric emptying!
- Metoclopramide 10mg PO QID
- Drug of choice; best evidence for positive effect
- Works as dopamine antagonist and promotes Ach secretion in GI sm. mm. cells
- Contraindications: GI bleed, obstruction, h/o epilepsy, parkinson's
- Side f/x: drowsiness, extrapyramidal sx, amenorrhea, galactorrhea
- Unclear whether it's effective long-term
- Cisapride 10-20mg TID
- Good alternative to metoclopramide
- Increases Ach release from myenteric plexus cells
- +/- change in symptoms in well-designed studies
- Can cause diarrhea, borborygmi
- Probably does work long-term
- Domperidone 10 QID - 20 TID
- A dopamine antagonist
- Not clearly better than placebo in double-blind trials
- Side f/x include dry mouth but no neuro f/x
- Erythromycin 250 TID
- Acts as a "motilin" agonist
- Analogues without antibiotic effects may be promising
- No studies of sx improvement as of 1990? Improves gastric emptying c/w placebo (NEJM 322:1028, 1990)
- Renzapride
- A dopamine agonist
- Only one study as of 1993, showing decreased gastric emptying time; sx not explored
- Gastric pacing in refractory cases, e.g. pts requiring tube feeds