Efficacy of indapamide in central diabetes insipidus

Background: Central diabetes insipidus (CDI) results from deficient vasopre ssin (antidiuretic hormone) secretion and causes polydipsia and polyuria. D esmoprossin, a synthetic analog of vasopressin, is the drug of choice in th e treatment of CDI, but in mild cases, there are alternative drugs that can be used, including chlorpropamide, carbamazepine, and thiazides. Methods: In this study, we investigated the efficacy of treatment with inda pamide, which is an antihypertensive diuretic oral agent, in 20 consecutive patients with CDI. The diagnosis of CDI was established by water-deprivati on and vasopressin tests. Before the study, serum and urinary osmolality, d aily urinary volume, and serum electrolyte levels were measured in all 20 p atients. Indapamide (2.5 mg/d) was administered for 10 days, and then the i nvestigations were performed again; for purposes of comparison, 250 mg/d of chlorpropamide was also administered to ii of the 20 patients who had been given indapamide. Results: Indapamide revealed a 40.56% +/- 9.70% (mean SD) (range, 19.6%-55. 0%) reduction in 24-hour urinary volume and an increase in urinary osmolali ty, as well as a decrease in serum osmolality, and was as effective as chlo rpropamide (P<.05) in the treatment of CDI. Conclusion: Because of its low cost and lack of significant adverse effects , indapamide may be a suitable, easy-to-use alternative oral agent for some patients with CDI.