Generic name: Tolvaptan 30 mg Brand name: Natrise 30 Tablet (Sun Pharma & other marketers) Dosage form: Oral tablet (film‑coated tablet) Composition : Active ingredient: Tolvaptan — 30 mg per tablet Therapeutic Classification Therapeutic class: Vasopressin receptor antagonist / Electrolyte balance agent Action class: Vasopressin (V2) receptor antagonist – increases free water excretion without significant loss of sodium or potassium Route & Administration : Route: Oral (by mouth) Administration: Swallow whole with water; doses are usually once daily or as instructed by a physician Natrise 30 Tablet is a medicine used in the treatment of low levels of sodium in the blood. It treats low levels of sodium in the blood, which can result from conditions such as heart failure, cirrhosis, and syndrome of inappropriate antidiuretic hormone (SIADH). Uses : Treatment of hyponatremia (low sodium levels in the blood): Helps raise sodium levels in adults with conditions where sodium is dangerously low. This can happen in: Heart failure Liver disease / cirrhosis Syndrome of Inappropriate Antidiuretic Hormone (SIADH) By increasing urine output (without losing sodium), it reduces excess water in the body and improves sodium balance. Slowing progression of autosomal dominant polycystic kidney disease (ADPKD): It may be used to slow kidney cyst growth and decline in kidney function in adults with rapidly progressing ADPKD How It Works : Tolavaptan in Natrise blocks the effect of vasopressin (antidiuretic hormone), reducing water reabsorption in kidneys, leading to increased urine production (aquaresis) and raised serum sodium levels without significant loss of electrolytes.