Bioavailability and pharmacokinetics of desmopressin in elderly men.

The bioavailability and pharmacokinetics of desmopressin (Minirin, DDAVP) have been studied in elderly males, aged between 55 and 75 years. In a four-way randomised study, subjects received a dose of desmopressin either intravenously (2 micrograms) or orally (200 micrograms) and either at 11 am or 10 pm. Daytime and night-time urine samples were collected both with and without desmopressin treatment. Intravenous doses of desmopressin were observed to have a longer duration of action than when the dose was given orally. These differences in efficacy may be attributable to differences in the bioavailability of desmopressin after intravenous or oral treatment.