Acute effect of clonidine on gastric emptying in patients with diabetic gastropathy and controls.

BACKGROUND

The treatments available for diabetic gastropathy are frequently ineffective. Clinical observations suggest that clonidine, an a-2 adrenergic agonist, may improve diabetic gastropathy symptoms.

AIMS

To establish whether a single oral dose of clonidine alters the gastric emptying of a solid meal in 10 patients with diabetic gastropathy and their matched controls. A secondary goal was to compare two methods of analysis of the data from gastric emptying studies.

METHODS

Clonidine, 0.3 mg, or a matched placebo were administered orally in a double-blind fashion.

RESULTS

Only three of the 10 patients showed an increased gastric residual volume. Gastric emptying rates were comparable in patients and controls. Clonidine had no significant effect on gastric emptying in the controls but increased t1/2 values in the patient group. This effect just reached statistical significance only when calculated by the power exponential method (P=0.05 but not by the linear component model.

CONCLUSIONS

Delayed gastric emptying is not an invariable characteristic of symptomatic diabetic gastropathy. Clonidine, given as a single dose of 0.3 mg orally, has no gastric prokinetic effects. It may act on gastric afferent innervation or, more likely, at a central site to reduce nausea and vomiting. The analysis of gastric emptying data by the power exponential and the two linear component methods yields equivalent results.