Editing Functional: Pharmacological Management of LUTS (section)

=== Desmopressin ===
* '''Mechanism of action:'''
** '''Analogue of the endogenous hormone''' '''vasopressin (also known as antidiuretic hormone).'''
*** Vasopressin
**** Functions (2):
****# Causes contraction of vascular smooth muscle
****# Stimulates water reabsorption from the collecting ducts
**** Release stimulated by:
***** Hyperosmolality
***** Hypovolemia
***** Stress
***** Nausea
***** Pregnancy
***** Hypoglycemia
***** Nicotine
***** Morphine
***** Other drugs
**** Release inhibited by:
***** Hypoosmolality
***** Hypervolemia
***** Ethanol
***** Phenytoin
* '''Pharmacology'''
** '''More powerful and longer-lasting antidiuretic action than vasopressin/anti-diuretic hormone''' due to selectivity for antidiuretic over vasopressor effects.
** '''Fast onset of action, with urine production decreasing within 30 minutes of oral administration'''
** Available in formulations for oral, parenteral, and nasal administration.
*** '''Because symptomatic hyponatremia with water intoxication,''' which is the only serious adverse event reported in children, '''occurred after intranasal or intravenous administration of desmopressin,''' the FDA and the European Medicines Agency (EMA) '''removed the indication for the treatment of primary nocturnal enuresis from all intranasal preparations of desmopressin.''' '''An oral lyophilisate formulation (MELT) requiring no concomitant fluid intake is currently available'''
* '''Efficacy'''
** '''Nocturia'''
*** '''Desmopressin is the most common vasopressin analogue used to treat nocturia in children and adults.'''
**** '''Decreased vasopressin levels are believed to be important in the pathophysiology of some forms of polyuria, specifically nocturnal polyuria.'''
*** '''Results in significant improvements in reducing nocturnal voids and increasing the hours of undisturbed sleep'''.
*** '''Generally well tolerated in all the studies on nocturia.'''
** '''Enuresis'''
*** In children, effective in reducing bedwetting. However, there was no effect after discontinuation of treatment, indicating that '''desmopressin suppresses the symptom of enuresis but does not cure the underlying cause.'''
**** In addition, not all children responded sufficiently to desmopressin monotherapy.
**** '''The combination of desmopressin and an enuresis alarm resulted in a greatly improved short-term success rate and decreased relapse rates'''
* '''Contraindications (drug monograph):'''
** '''Patients with type IIB or platelet-type (pseudo) Willerbrand disease, because of the risk of platelet aggregation and thrombocytopenia'''
** '''Any condition associated with impaired water excretion, such as:'''
*** '''Hyponatremia'''
*** '''Severe liver disease'''
*** '''[Hydro]nephrosis'''
*** '''Cardiac insufficiency'''
*** '''Chronic renal insufficiency'''
*** '''Congestive heart failure'''
*** '''Habitual or psychogenic polydypsia'''
** '''Any medical conditions which lead to sodium losing states such as:'''
*** '''Vomiting'''
*** '''Diarrhea'''
*** '''Bulimia'''
*** '''Anorexia nervosa'''
*** '''Adrenocortical insufficiency'''
*** '''Salt losing nephropathies'''
** '''Lactose intolerance/allergies'''
* '''Adverse events'''
** '''Hyponatremia'''
*** '''Can lead to a variety of adverse events ranging from mild headache, anorexia, nausea, and vomiting to loss of consciousness, seizures, and death'''
*** '''Usually occurs soon after treatment is initiated'''
*** '''Risk factors:'''
***# '''Increasing age'''
***# '''Female gender'''
***# '''Cardiac disease'''
***# '''Increasing 24-hour urine volume'''
* '''Dosing'''
** '''Females demonstrate increased sensitivity to demopression; recommended efficacious doses are 25 μg MELT for females and 50 to 100 μg MELT for males'''
** '''Prior to initiation, a serum sodium should be obtained at baseline, then again after initiation. Serum sodium should be assessed regularly, at least every 6 months with long-term desmopressin administration'''
** '''Initiation of desmopressin is currently not indicated for patients age ≥ 65''' (different than CUA guidelines, see below)
** '''2018 CUA MLUTS Guidelines'''
*** '''While the risk of hyponatremia is low in men with normal baseline serum sodium, sodium must be checked at baseline and 4–8 days as well as 30 days after initiation of treatment in (2):'''
***# '''All men taking desmopressin melts'''
***# '''Men ≥65 years taking 50 μg oral disintegrating tablet'''
**** Note that these guidelines are for male LUTS and therefore recommendations for females are not provided.