Purpose: Milk thistle or its purified extract, silymarin (Silybum marianum), is widely used in treating acute or
chronic hepatitis. Although silymarin is hepatoprotective in animal experiments and some human hepatotoxic
exposures, its efficacy in ameliorating the symptoms of acute clinical hepatitis remains inconclusive. In this study, our
purpose was to determine whether silymarin improves symptoms, signs and laboratory test results in patients with
acute clinical hepatitis, regardless of etiology.
Methods: This is a randomized, placebo-controlled trial in which participants, treating physicians and data
management staff were blinded to treatment group. The study was conducted at two fever hospitals in Tanta and
Banha, Egypt where patients with symptoms compatible with acute clinical hepatitis and serum alanine
aminotransferase (ALT) levels 42.5 times the upper limit of normal were enrolled. The intervention consisted of
three times daily ingestion of either a standard recommended dose of 140 mg of silymarin (Legalons, MADAUS
GmbH, Cologne, Germany), or a vitamin placebo for four weeks with an additional four-week follow-up. The primary
outcomes were symptoms and signs of acute hepatitis and results of liver function tests on days 2, 4 and 7 and weeks 2,
4, and 8. Side-effects and adverse events were ascertained by self-report.
Results: From July 2003 through October 2005, 105 eligible patients were enrolled after providing informed consent.
No adverse events were noted and both silymarin and placebo were well tolerated. Patients randomized to the
silymarin group had quicker resolution of symptoms related to biliary retention: dark urine (p 0.013), jaundice
(p 0.02) and scleral icterus (p 0.043). There was a reduction in indirect bilirubin among those assigned to silymarin
(p 0.012), but other variables including direct bilirubin, ALT and aspartate aminotransferase (AST) were not
significantly reduced.