Oral DDAVP is a good alternative therapy for patients with central diabetes insipidus: experience of five-year treatment.

We studied the efficacy and safety of oral 1-deamino-8-D-arginine-vasopressin (DDAVP) tablets in 9 patients, aged 17-36 years, with central diabetes insipidus (DI). The tablet contained 100 microg of desmopressin acetate. Maximum plasma concentration was obtained at 90 min after a single oral administration of 100 microg DDAVP with a mean plasma level of 14.7 +/- 5.4 (range: 5.3-50.9) pg/ml. The onset of action was observed 2 h after oral administration, while the maximum effect was obtained at 4 h. Mean urine volume in patients decreased significantly from 402 +/- 52 to 26 +/- 3 ml/hr and urine osmolality increased from 91 +/- 8 to 732 +/- 21 mosm/kg at 4 h after the intake of oral DDAVP. Plasma osmolality level and serum sodium concentration remained unchanged throughout the study. Long-term treatment for 5 years with oral DDAVP resulted in control of diuresis in 8 of the 9 patients. The average oral DDAVP dose required to obtain this control was 19 +/- 2 (range: 15-30) times more than that of prior intranasal treatment. No adverse effects were observed during this follow-up period. These results indicate that oral DDAVP is a safe therapeutic agent that may be a good alternative treatment of central DI, particularly in patients who have chronic rhinitis and visual disturbances.