The Federal Drug Administration (FDA) (www.fda.gov) has issued a safety alert for the drug tolvaptan, a popular diuretic drug used in the treatment of hyponatremia. The safety alert warns healthcare professionals of potentially irreversible liver damage linked to use of the drug.
Tolvaptan, which is sold under the brand name Samsca, is used in the treatment of hypervolemic and euvolemic hyponatremia. Samsca works as a selective vasopressin V2-receptor antagonist. Hyponatremia is a condition in which there is a low amount of sodium in the blood. Hyponatremia can occur due to use of other medical treatment drugs, such as diuretics or may result from cirrhosis of the liver, kidney disease, congestive heart failure, as well as other medical conditions.
Study Links Samsca to Potentially Fatal Liver Injury
Samsca is manufactured by Otsuka Pharmaceutical Co., Ltd. of Rockville, Md. In addition, the company has issued a letter to healthcare professionals notifying them of significant liver injury associated with the use of Samsca in a recent trial study.
The double-blind, 3-year, placebo-controlled trial involved 1400 patients suffering from autosomal dominant polycystic kidney disease (ADPKD). Results of the study indicate that Samsca does have the potential to cause liver injury. In some cases, the damage can be irreversible and potentially fatal.
Although Samsca is not approved for the treatment of ADPKD, the warning has been issued as a precaution to all patients being administered the drug.
What Healthcare Providers Should Do
Otsuka Pharmaceutical and the FDA recommend that patients who report the following symptoms have their healthcare providers perform liver tests as soon as possible. Symptoms of liver injury include:
- Right upper abdominal pain
- Darkened urine
If patients are exhibiting symptoms of liver damage, Samsca should be discontinued immediately. Treatment for liver injury should be initiated and Samsca should not be re-prescribed until the cause of the injury is definitively established.
Patients, as well as healthcare professionals, should report incidents of liver injury or other adverse events potentially related to the use of Samsca to Otsuka Pharmaceutical or directly to the FDA.