Successful long-term treatment of congenital nephrogenic diabetes insipidus in a dog

A two-year-old intact male shiba inu dog with excessive polyuria and polydi psia (PU-PD) was diagnosed as having congenital nephrogenic diabetes insipi dus based on clinical findings, the results of urinalysis, blood examinatio ns, a modified water deprivation test and a low dose dexamethasone suppress ion test. The owner was advised to provide adequate access to drinking wate r, and treatment with a low dose of hydrochlorothiazide (2 mg/kg, twice dai ly) together with a low sodium diet was initiated. As a result, the daily w ater intake decreased significantly from 6500 to 7500 ml/day (800 to 980 ml /kg/day) to 1400 to 1900 ml/day (170 to 230 ml/kg/day) and the clinical sig ns associated with the PU-PD and dehydration improved over the following tw o years.