Nonpharmacologic and especially pharmacologic treatment options are available for nocturnal polyuria. Desmopressin represents the basis of pharmacologic treatment.
Desmopressin acetate is a synthetic analogue of arginine vasopressin with high affinity to V2 receptors with antidiuretic effect. It is the only medicament currently registered for antidiuretic treatment.
Desmopressin has not any relevant affinity to V1 receptors, and therefore there is no hypertensive effect in contrary to natural vasopressin.Desmopressin use before a bedtime leads to reduced production of urine during a sleep, therefore time between desires to void is prolonged and number of nocturia is reduced. Clinical effect, in a meaning of reduced urine production and increased osmolality of urine, lasts approximately 8-12 hours.
In the treatment of nocturnal polyuria desmopressin is used orally one hour before a bedtime. It is essential to titrate an ideal dose, the initial dose is 60 μg of MELT formula (fast melting oral formulation) and it can be increased according to the clinical effect up to the maximal recommended daily dose 240 μg.
Patients treated with desmopressin should cut down a fluid intake 1 hour before and 8 hours after the use of desmopressin. Total number of adverse events connected with desmopressin treatment in clinical studies was higher compared to placebo but the side effects were mostly mild.
The most common adverse events were headaches, nausea, diarrhoea, abdominal pain, dry mouth and hyponatremia both in the short-term and long-term clinical trials. Hyponatremia was observed mainly in patients over 65 year of age.
Therefore treatment with desmopressin should not be commended in patients over 65 year of age without close monitoring of the natrium level in serum and all patients should be informed about the first symptoms of hyponatremia - headache, nausea and insomnia. According to Evidence Based Medicine, the level of evidence for treatment of nocturnal polyuria with desmopressin is 1b and the grade of ecommendation for treatment is A