Chronic administration of levosulpiride and glycemic control in IDDM patients with gastroparesis.

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. 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. 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. 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.