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Hepatic Injury

  • There have been post-marketing reports of hospitalization and rarely death due to liver failure in patients taking flutamide. Evidence of hepatic injury included elevated serum transaminase levels, jaundice, hepatic encephalopathy and death related to acute hepatic failure.
  • The hepatic injury was reversible after discontinuation of therapy in some patients. Approximately half of the reported cases occurred within the initial 3 months of treatment with flutamide.
  • Serum transaminase levels should be measured prior to starting treatment with flutamide.
  • Flutamide is not recommended in patients whose ALT values exceed twice the upper limit of normal.
  • Serum transaminase levels should then be measured monthly for the first 4 months of therapy, and periodically thereafter. Liver function tests also should be obtained at the first signs and symptoms suggestive of liver dysfunction, e.g., nausea, vomiting, abdominal pain, fatigue, anorexia, “flu-like” symptoms, hyperbilirubinuria, jaundice or right upper quadrant tenderness.
  • If at any time, a patient has jaundice, or their ALT rises above 2 times the upper limit of normal, flutamide should be immediately discontinued with close follow-up of liver function tests until resolution.


  • Perform baseline serum transaminase levels prior to therapy and monthly for the first 4 months and periodically, thereafter or when clinically necessary.
  • Not recommended if ALT > 2 times upper limit of normal.
  • Obtain LFTs at first signs and symptoms of liver dysfunction.
  • Discontinue if jaundice occurs or ALT > 2 times upper limit of normal

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Additional Information

Updated January 2018