Influence of erythromycin on gastric emptying and meal related symptoms in functional dyspepsia with delayed gastric emptying

Background and aims: Although delayed gastric emptying is considered a major pathophysiological mechanism in functional dyspepsia, the efficacy of prokinetic drugs has not been established. Recent studies using macrolide prokinetics were negative but receptor desensitisation may have played a role. The aim of the present study was to evaluate the influence on meal induced symptoms of acutely administered erythromycin in patients with gastroparesis. Methods: In 20 patients with functional dyspepsia, gastric emptying was studied twice using the C-14 octanoic acid and C-13 glycin breath test to establish the reproducibility of the test. Breath samples were taken before the meal and at 15 minute intervals for a period of 240 minutes postprandially. At each breath sampling, the patient was asked to grade the intensity (0-3) of six dyspeptic symptoms. Twenty four patients ( three men, mean age 43.5 ( 3) years) with dyspeptic symptoms and delayed gastric emptying were studied twice after pretreatment with saline or erythromycin intravenously. Results: Meal related symptom severity scores were reproducible. Treatment with erythromycin significantly enhanced solid and liquid gastric emptying (t(1/2) 146 ( 27) v 72 ( 7) minutes, respectively (p<0.01), and 87 (6) v 63 (5) minutes (p<0.001)). Only the severity of bloating was significantly improved by erythromycin (23 (3.9) v 14.5 (2.7); p<0.01); all other symptoms and the cumulative meal related symptom score were not altered by erythromycin. Conclusions: In a setting where desensitisation played no role, erythromycin enhanced gastric emptying was not associated with a beneficial effect on meal related symptom severity.