Silymarin is the main active constituent found in milk thistle (Silybum marianum). Milk thistle has been used historically to support liver health and various liver disorders and new research is supporting its historical use.
Hepatitis, or inflammation of the liver, can be caused by bacteria, viruses, excessive alcohol intake, and some medications. Symptoms of hepatitis include jaundice (yellowing of the skin), dark urine, and scleral icterus (yellowing of the whites of the eyes). In a recently published clinical trial, silymarin supplementation was investigated in patients with acute clinical hepatitis of various causes. In this randomized, placebo-controlled trial, 105 subjects were enrolled with symptoms of acute hepatitis as well as elevated levels of the liver enzyme serum alanine aminotransferase (ALT), which were greater than 2.5 times the upper limit of normal. The subjects were supplemented with 140 mg of silymarin three times per day or a placebo for 4 weeks with a 4-week follow-up period. Liver tests were run on days 2, 4, and 7 and during weeks 2, 4, and 8.
The results showed that the subjects receiving silymarin had a quicker resolution of symptoms including jaundice, dark urine, and scleral icterus compared to the placebo group. The group supplemented with silymarin also showed a decrease in indirect bilirubin, the yellow break-down product of heme found in hemoglobin, although there was no change in the other liver function tests such as direct bilirubin, ALT and aspartate aminotransferase (AST). No adverse events were reported.
The researchers stated, "Patients receiving silymarin had earlier improvement in subjective and clinical markers of biliary excretion. Despite a modest sample size and multiple etiologies for acute clinical hepatitis, our results suggest that standard recommended doses of silymarin are safe and may be potentially effective in improving symptoms of acute clinical hepatitis despite lack of a detectable effect on biomarkers of the underlying hepatocellular inflammatory process."
Reference:
El-Kamary SS, Shardell MD, Abdel-Hamid M, Ismail S, El-Ateek M, Metwally M, Mikhail N, Hashem M, Mousa A, Aboul-Fotouh A, El-Kassas M, Esmat G, Strickland GT. A randomized controlled trial to assess the safety and efficacy of silymarin on symptoms, signs and biomarkers of acute hepatitis. Phytomedicine. 2009 May;16(5):391-400.
Silymarin is available here as a stand-alone supplement. Milk thistle is also found in HepatoGen along with other liver-supporting ingredients.