A 58-year-old man is brought to the emergency department after a witnessed tonic-clonic seizure. the patient has worsening serum electrolyte disturbances. Further evaluation reveals the cause is inappropriate antidiuretic hormone secretion. Treatment with a vasopressin V2 receptor antagonist is initiated. Which of the following changes are most likely to occur as a direct result of the administered medication?

Question

Quizplus · Accepted Answer

Eductional Objective: Vaptans (eg, tolvaptan) are vasopressin V2 receptor antagonists (ie, aquaretics) used to treat hyponatremia. Vaptans block the effects of antidiuretic hormone (vasopressin), increasing renal free water excretion without directly affecting excretion of sodium or potassium. Diuresis of free water with vaptans results in increased plasma osmolality, increased serum sodium, increased urine output, and lowered urine osmolality.

A 58-Year-Old Man Is Brought to the Emergency Department After