What is desmopressin used for?
Desmopressin is a synthetic albumin (protein) and structurally related to the endogenous peptide hormone vasopressin (antidiuretic hormone also, ADH, called). Desmopressin inhibits the excretion of water and is used as a drug.
Desmopressin mechanism of action
Desmopressin is a synthetic analogue of the endogenous arginine-vasopressin and an agonist to the AVP receptors. It differs from this physiological hormone from the pituitary gland but in receptor affinity: While AVP with similar affinity to the V1, which is mainly responsible for vasoconstriction, such binds to the V2 receptor, desmopressin is non-affine the V2 receptor and neglected the V1.
The AVP receptor 2 is again mainly responsible for water retention in the collecting ducts of the kidney. When activated, it causes the installation of water channels (aquaporins) in the cell membranes, which allow water molecules to pass. As a result, the urine is drained / thickened and retain more water in the body.
In addition, there are other effects of V2: It triggers the release of von Willebrand factor and expression of P-selectin during exocytosis of Weibel-Palade bodies of endothelial cells.
Application
Desmopressin is an anti-diuretic. It inhibits occurring in a central diabetes insipidus typically massive water excretion. Characterized the quality of life of affected patients is significantly improved.
Also for the treatment of polyuria and polydipsia traumatic it is approved, as well as in other diseases associated with ADH deficiency, as od after surgery in the pituitary gland. Craniocerebral trauma.
And as a diagnostic tool for the differential diagnosis of diabetes insipidus.
Another application is the treatment of nighttime bedwetting (nocturnal enuresis).
Desmopressin can also be given as Antihämorrhagikum eg hemophilia uremic Thombozytopathie or Von Willebrand disease.
Desmopressin side effects
The common side effects will generally be related to the pharmacodynamics together. Especially with increased fluid intake is leading to increased water retention (Desmopressin is a highly potent anti-diuretic), thereby increasing volume with relative electrolyte depletion. Warning signs of this are headache, nausea / vomiting, and weight gain. In rare severe cases it can lead to cerebral edema, leading partly connected with seizures or awareness restrictions.
In addition, there are rare side effects such as allergies and Herzkreislaufprobeme (eg angina pectoris), which are associated with the increase in blood pressure.
Desmopressin dosage
Desmopressin is one of the few drugs for which a nasal spray is available next to the tablets and orodispersible tablet. Because of the low molecular weight hormone occurs well enough through the nasal mucosa into the blood stream. However, the indication for nocturnal enuresis is retracted for the nasal spray, as the tablet form has been found to be safer to use. The orodispersible tablet, which is now approved in Germany since 1 June 2011 and is already longer sold in other countries, is to ensure a safer absorption and effect. The improved bioavailability lower drug loading is possible for the same effect. DDAVP is furthermore available as an infusion solution for intravenous and subcutaneous administration.