National Center for Complementary and Alternative Medicine (NCCAM)

NIH…Turning Discovery Into Health®

Follow NCCAM: Subscribe to our email update Subscribe to the NCCAM RSS feed Follow NCCAM on TwitterRead our disclaimer about external links Follow NCCAM on FacebookRead our disclaimer about external links


National Institutes of Health • National Center for Complementary and Alternative Medicine

NCCAM Clinical Digest

Hepatitis C and CAM :
What the Science Says

March 2011
An NCCAM research nurse practitioner talking to a patient about CAM use.

A review of the scientific evidence on CAM and hepatitis C found the following:

  • No CAM treatment has been scientifically proven to successfully treat hepatitis C.
  • A 2003 analysis of results from 13 clinical trials testing the effects of various medicinal herbs on hepatitis C concluded that there is not enough evidence to support using herbs to treat the disease.
  • Two other reviews that covered a variety of CAM modalities for hepatitis C concluded that conventional therapies are the only scientifically proven treatments for the disease.
  • In a 2002 NIH consensus statement on the management of hepatitis C, a panel of medical and scientific experts concluded that "alternative and nontraditional medicines" should be studied. Participants in a 2001 NIH research workshop on the benefits and risks of CAM therapies for chronic liver disease recommended research support for related laboratory and clinical studies.

The following summarizes what is known about the safety and effectiveness of milk thistle and some of the other CAM products that people with hepatitis C use.

Milk Thistle

® 2004 Horticopia, Inc.
Photography by Robert E. Lyons

Milk thistle (scientific name Silybum marianum) is a plant from the aster family. Silymarin, the active extract of milk thistle, is believed to be responsible for the herb's medicinal qualities. Milk thistle has been used in Europe as a treatment for liver disease and jaundice since the 16th century. In the United States, silymarin is the most popular CAM product taken by people with liver disease.

Laboratory studies suggest that milk thistle may benefit the liver by protecting and promoting the growth of liver cells, fighting oxidation (a chemical process that can damage cells), and inhibiting inflammation. Study results from small clinical trials on milk thistle for liver diseases have been mixed; however, most of these studies have not been rigorously designed, or they have looked at various types of liver diseases—not just hepatitis C. High-quality, well-designed clinical trials have not proven that milk thistle or silymarin is beneficial for treating hepatitis C. The HALT-C study mentioned above found that silymarin use by hepatitis C patients was associated with fewer and milder symptoms of liver disease and somewhat better quality of life, but there was no change in virus activity or liver inflammation. The researchers emphasize that this was a retrospective study, not a controlled clinical trial. More research on milk thistle for hepatitis C is needed before a recommendation can be made.

Milk thistle is generally well tolerated and has shown few side effects in clinical trials involving patients with liver disease. It may cause a laxative effect, nausea, diarrhea, abdominal bloating, fullness, and pain, and it can produce allergic reactions (especially among people who are allergic to plants in the same family, such as ragweed, chrysanthemum, marigold, and daisy).

Other supplements are also being studied for hepatitis C. For example:

  • Ginseng has shown some beneficial effects on the liver in laboratory studies but has not yet shown effects in people.
  • Thymus extract and colloidal silver are sometimes marketed for the treatment of hepatitis C, but there is currently no research to support their use for this purpose. Colloidal silver products can cause serious side effects (for more information, see the NCCAM fact sheet Colloidal Silver Products).
  • People with chronic liver disease sometimes use licorice root or its extract glycyrrhizin. Some studies, reported from outside the United States, have looked at glycyrrhizin administered intravenously for hepatitis C. Preliminary evidence from these studies suggests that glycyrrhizin may have beneficial effects against hepatitis C. However, additional research is needed before reaching any conclusions.
  • Preliminary studies conducted primarily outside the United States have examined the potential of the following herbal products for treating chronic hepatitis C: lactoferrin, TJ-108 (a mixture of herbs used in Japanese Kampo medicine), schisandra, and oxymatrine (an extract from the sophora root). More research is needed before the safety and effectiveness of these products can be fully evaluated.

NCCAM Clinical Digest is a service of the National Center for Complementary and Alternative Medicine, NIH, DHHS. NCCAM Clinical Digest, a monthly e-newsletter, offers evidence-based information on CAM, including scientific literature searches, summaries of NCCAM-funded research, fact sheets for patients, and more.

The National Center for Complementary and Alternative Medicine is dedicated to exploring complementary and alternative healing practices in the context of rigorous science, training CAM researchers, and disseminating authoritative information to the public and professionals. For additional information, call NCCAM's Clearinghouse toll-free at 1-888-644-6226, or visit the NCCAM Web site at NCCAM is 1 of 27 institutes and centers at the National Institutes of Health, the Federal focal point for medical research in the United States.



Content is in the public domain and may be reprinted, except if marked as copyrighted (©). Please credit the National Center for Complementary and Alternative Medicine as the source. All copyrighted material is the property of its respective owners and may not be reprinted without their permission.

Follow NCCAM on:

Twitter Twitter at

Facebook Facebook at

YouTube YouTube at