Antidiuretika

Antidiuretika, or antidiuretic drugs, are substances that reduce urine production by promoting water reabsorption in the kidneys. The principal endogenous regulator is vasopressin (antidiuretic hormone, AVP), which acts on V2 receptors in the collecting ducts to increase aquaporin-2 channels and water reabsorption, concentrating urine and decreasing its volume.

Clinical use focuses on disorders of excessive urination such as central diabetes insipidus, where vasopressin or its synthetic analog desmopressin is used to reduce urine output. Desmopressin is more selective for V2 receptors and is commonly preferred due to fewer vasoconstrictive effects. In bedwetting (nocturnal enuresis) and certain bleeding disorders, desmopressin is also used.

Medications include vasopressin and desmopressin; other vasopressors such as terlipressin have antidiuretic properties but are primarily used for circulatory support rather than to reduce urine output. Administration routes vary: desmopressin can be given intranasally, orally, or by injection; vasopressin and terlipressin are typically given parenterally.

Important adverse effects relate to excessive water retention, leading to hyponatremia, seizures in severe cases, particularly if fluid intake is high or in vulnerable populations. Hyponatremia risk requires monitoring of serum sodium, especially in the elderly or patients with comorbidities.

Notes: The term antidiuretika is used in several languages to refer to these agents. They are not effective for polyuria due to osmotic causes or nephrogenic diabetes insipidus that does not respond to vasopressin.