Tolvaptan

Tolvaptan is an orally administered medication used for the treatment of hyponatremia, a condition characterized by low levels of sodium in the blood. It is a selective vasopressin V2 receptor antagonist, which means it works by blocking the action of the hormone vasopressin, also known as antidiuretic hormone (ADH).
In the kidneys, vasopressin promotes water reabsorption, leading to increased water retention and dilution of the blood. In hyponatremia, this can further lower the blood sodium concentration. By blocking the action of vasopressin, tolvaptan inhibits water reabsorption, promoting the excretion of excess water and increasing blood sodium levels.
Tolvaptan is particularly useful in patients with euvolemic hyponatremia, a form of the condition where there is no significant change in blood volume. It is also indicated for the treatment of hyponatremia in patients with heart failure who have a reduced ejection fraction, a measure of the heart’s pumping efficiency.
Tolvaptan is available in tablet form and is typically administered once daily. The medication should be used under the supervision of a healthcare professional, as it can cause side effects such as thirst, nausea, and increased urination. Monitor blood sodium levels regularly while taking tolvaptan to ensure safe and effective treatment.