Objective: We evaluated the effect of chronic administration of levosulpiride, a prokinetic drug that is a selective antagonist for D2 dopamine receptors, on the glycemic control of IDDM subjects.
Research design and methods: The study was performed on 40 long-standing IDDM subjects with clinical signs of autonomic neuropathy and delayed gastric emptying. Gastric emptying time and glycemic parameters (diurnal glycemic profile and HbA1c) were checked under double-blind conditions before and after the administration of levosulpiride at the dosage of 25 mg t.i.d. orally for 6 months, or placebo.
Results: No significant differences were noted in the glycemic and HbA1c values before and after 6 months of placebo administration. In contrast, after 6 months of levosulpiride, glycemic control had improved (HbA1c 6.7 +/- 0.4 and 5.7 +/- 0.3%, P < 0.01; mean daily glycemia 10.9 +/- 0.8 and 8.8 +/- 0.4 mmol/l, P < 0.05, at the start and at the end of the study), while the dosage of injected insulin (0.65 +/- 0.02 IU.kg-1.day-1) and the number of severe hypoglycemic episodes remained unchanged. After 6 months of levosulpiride therapy, the time of gastric emptying was significantly reduced from 321 +/- 14 to 261 +/- 9 min (P < 0.001) and dyspeptic symptoms had improved.
Conclusions: Our results show the importance of gastric emptying in the maintenance of glycemic control and the usefulness of chronic administration of levosulpiride in diabetic subjects with gastroparesis.