Last week, the FDA issued a warning of potential risk of liver injury from Samsca (tolvaptan) manufactured by Otsuka America Pharmaceutical Inc.
Samsca (tolvaptan) is used to treat hyponatremia (low levels of sodium in your blood) in patients with heart failure or liver disease. The FDA warning stated that in a double blind, 3-year, placebo-controlled trial of 1400 patients with Autosomal Dominant Polycystic Kidney Disease, 3 patients treated with Samsca developed significant increases in liver enzymes (specifically, serum alanine aminotransferase and serum total bilirubin).
Most of these abnormalities were seen in the first 18 months of treatment. However, all 3 patients improved after discontinuing Samsca. It is a small number of patients, to be sure, but it’s hard to think that it’s a coincidence.
The FDA stated from its findings that Samsca (tolvaptan) has the potential to cause irreversible and even fatal liver injury. Patients taking Samsca should consult a doctor right away if symptoms occur such as liver injury, fatigue, anorexia, right upper abdominal discomfort, dark urine, or jaundice. If a liver abnormality is suspected, the FDA warns that “Samsca should be promptly discontinued, appropriate treatment should be instituted, and investigations should be performed to determine probable cause.” Patients should avoid Samsca until it is determined that the liver injury was not caused by Samsca.
But first things first: if you’ve been taking Samsca (tolvaptan), you are going to want to listen to the FDA and talk to your doctor about any effects and symptoms you may be experiencing. You may also report adverse side effects and symptoms to the FDA.