The pharmacokinetic profile of desmopressin is biexponential. Terminal half-life was longer at night than in the daytime, but the difference is considered too small to be of clinical importance. The plasma levels given by the intravenous dose resulted in a duration of action of 12 h or more. Despite low bioavailability, the pharmacodynamic effects of oral desmopressin were similar in magnitude to those after intravenous dose at night and during the first 6 h after daytime administration.

In healthy males with occasional nocturia, the occurrence of nocturia seems to be associated with a blunting of the circadian rhythm of diuresis and increased arterial blood pressures during the night. These findings may implicate a role for a baroregulatory related mechanism in nocturia.

Antidiuresis, using oral desmopressin tablets, is a novel, feasible and safe (short-term basis) method of treatment for adults with OAB, and could be considered in the armamentarium of drugs available for the treatment of OAB.

This urodynamic study is one of the first to evaluate long-term urodynamic characteristics in patients treated with SRT. Several urodynamic parameters were affected. This indicates that SRT primarily affects bladder compliance, maximal cystometric capacity and bladder outlet obstruction. LUTS were proven to be strongly related to urodynamic parameters.

BackgroundSex hormones have a pronounced effect on arginine vasopressin (AVP), and therefore on the diurnal water homeostasis. Low and high levels of plasma-estradiol as seen in the follicular phase of the menstrual cycle may therefore alter the diurnal regulation of urine production. Furthermore the structural resemblance of oxytocin to vasopressin has led to speculations about the possible antidiuretic properties of oxytocin under normal physiological conditions. To elucidate the influence of high and low p-estradiol on the regulation of the diurnal urine production, 15 normal menstruating women (21–33 y) underwent two circadian in-patient investigations, both situated in follicular phase.MethodsAdmitting the participants solely in the follicular phase resulted in high and low plasma-estradiol whereas plasma-progesterone was similar. Urine and blood samples were taken at predetermined time points to determine plasma AVP, plasma oxytocin, plasma aldosterone, plasma natriuretic peptide (ANP), urinary solute excretions, and urinary excretions of prostaglandin E2 (PGE-2) and aquaporin-2 (AQP-2). Blood pressure was measured every hour.ResultsPlasma AVP, plasma aldosterone and plasma ANP were unaffected by the different levels of estradiol. All had marked circadian variations whereas oxytocin did not display any circadian rhythm. High estradiol resulted in lower p-osmolality and p-sodium reflecting the downward resetting of the osmoreceptors. Oxytocin did not correlate with either diuresis or urine osmolality. The diurnal urine production was similar in the two groups as were urine osmolality, excretion of PGE-2 and AQP-2. AQP-2 does not have a circadian rhythm and is not significantly correlated to either AVP or oxytocin under normal physiological conditions.ConclusionHigh and low level of estradiol has no influence on the circadian rhythm of AVP or the subsequent urine production. High p-estradiol resets the osmoreceptors for AVP release. Furthermore it appears that oxytocin under normal physiological conditions do not contribute to the overall antidiuretic effect.