• Plant Description
• What’s It Made Of?
• Available Forms
• How to Take It
• Possible Interactions
• Supporting Research
Milk thistle helps relieve the symptoms of hepatitis, cirrhosis, and inflammatory liver conditions. It is one of the most effective herbs known for treating liver disorders. Even the ancient Greeks knew the virtues of milk thistle for jaundice. Physicians of the Middle Ages used it for liver problems and other conditions, and nursing mothers took milk thistle leaf to increase their milk for breast-feeding.
Milk thistle protects the liver from harmful chemicals and alcohol. Silymarin is a more powerful antioxidant than vitamin C and vitamin E. Standardized extracts of milk thistle are beneficial for cirrhosis of the liver, chronic hepatitis B, chronic alcoholic liver diseases, and liver damage from toxins.
Silymarin is the most effective antidote to deathcap mushroom poisoning. Milk thistle standardized extract can stop deadly mushroom poisoning if you take it 10 minutes after you ingest deathcap (Amanita phalloides) mushrooms. Always get immediate medical attention if you eat poisonous mushrooms or any other toxic substance.
If you have a liver problem, or if you drink much alcohol (or drank too much in the past), your health care provider may recommend milk thistle for you. Milk thistle has demonstrated a protective effect on the liver following exposure to toxic doses of acetaminophen (a non-aspirin pain reliever). Likewise, milk thistle may protect against liver toxicity associated with phenothiazine medications (usually used to treat schizophrenia) and haloperidol.
Milk thistle is also beneficial if you need to increase your bile flow, and helps reduce the symptoms of psoriasis.
Milk thistle originally came from the Mediterranean. It is now widespread throughout the world, from Europe to Asia, and from Africa to North America. This stout thistle usually grows in dry, sunny areas. The stem branches at the top, and it reaches a height of 4 to 10 feet. The leaves are wide, with white blotches or veins. The flowers are red-purple. The small, hard-skinned fruit is brown, spotted, and shiny. Milk thistle is easy to grow, and it matures quickly, in less than a year.
What’s It Made Of?
Milk thistle fruit contains an active ingredient called silymarin. Silymarin is the liver-protecting compound inside milk thistle. Silymarin repairs liver cells damaged by alcohol and other toxic substances. Silymarin also keeps new liver cells from being destroyed by these same substances.
Milk thistle products are made from the seeds inside the fruit. The seeds contain 1.5% to 3% silymarin. Silymarin is actually made up of a group of compounds called flavonolignands. The most important flavonolignan is silybarin (sometimes called silybin). Other flavonolignans in silymarin are isosilybin, dehydrosilybin, silydianin, and silychristin.
Capsules of standardized dried herb (each capsule contains about 120 to 140 mg silymarin)
Several teas contain the standardized extract
How to Take It
You should always use standardized capsules whenever possible. This is because the silymarin in milk thistle seeds is hard to absorb. Silymarin can get into your system faster if it is concentrated, and it is most concentrated in standardized capsules. Try to avoid alcohol extracts.
The recommended dose of milk thistle is 12 to 15 g dried herb (200 to 400 mg silymarin) per day.
If you are taking milk thistle to protect your liver, you can take 120 mg silymarin (about 2 capsules) two times a day.
If you are taking milk thistle because your liver is damaged (from alcohol, drugs, or chemicals), the recommended dosage is 120 mg (about 3 capsules) three times a day.
There is a new form of milk thistle called silymarin-phosphatidylcholine complex. This is absorbed better than regular standardized milk thistle. In clinical trials, the silymarin-phosphatidylcholine complex worked better than silymarin by itself for treating liver disorders. A key element in cell membranes, phosphatidylcholine helps the silymarin attach easily to the cell membranes. This keeps toxins from getting inside liver cells.
The recommended dosage for silymarin-phosphatidylcholine complex is 100 to 200 mg two times per day.
According to the U.S. Food and Drug Administration, milk thistle is a dietary supplement. Milk thistle is safe when you follow the recommended dosage. Sometimes this herb has a mild laxative effect. If this happens, take some fiber such as guar gum, psyllium, oat bran, or pectin. The fiber should stop loose stools and any stomach discomfort.
Milk thistle may protect the kidneys against toxic side effects associated with chemotherapy treatment with cisplatin; however, a laboratory study revealed that the anticancer effect of cisplatin and ifosfamide was reduced in the presence of milk thistle. Therefore, you should consult with your healthcare provider before adding any new herbs or supplements to your existing medication regimen, especially if you are undergoing chemotherapy.
Milk thistle may also impact the effectiveness of cyclosporine. Consult with your healthcare provider before using milk thistle if you are currently being treated with cyclosporine.
Alarcón de la Lastra A, Martín M, Motilva V, et al. Gastroprotection induced by silymarin, the hepatoprotective principle of Silybum marianum in ischemia-reperfusion mucosal injury: role of neutrophils. Planta Med. 1995;61:116–119.
Bokemeyer C, Fels LM, DunnT, et al. Silibinin protects against cisplatin-induced nephrotoxicity without compromising cisplatin on isosfamide anti-tumor activity. Br J Cancer. 1996;74:2036–2041.
Campos R, Garrido A, Guerra R, et al. Silybin dihemisuccinate protects against glutathione depletion and lipid peroxidation induced by acetaminophen on rat liver. Planta Med. 1989;55:417–419.
Dorland Newman WA, ed. Dorland’s Illustrated Medical Dictionary. 25th ed. Philadelphia, Pa: WB Saunders. 1974.
Feher J, Deak G, Muzes G, Lang I, Neiderland V, Nekan K, et al. Hepatoprotective activity of silymarin therapy in patients with chronic alcoholic liver disease. Orv Hetil. 1990;130:51.
Ferenci P, Dragosics B, Dittrich H, Frank H., Benda L, Lochs H, et al. Randomized controlled trial of silymarin treatment in patients with cirrhosis of the liver. J Hepatol. 1989;9:105-13.
Flora K, Hahn M, Rosen H, Benner K. Milk thistle (Silybum marianum) for the therapy of liver disease. Am J Gastroenterol. 1998;93:139–43.
Gaedeke J, Fels LM, Bokemeyer C, et al. Cisplatin nephrotoxicity and protection by silibinin. Nephrol Dial Transplant. 1996;11:55–62.
Hobbs C. Milk Thistle: The Liver Herb. 2nd ed. Capitola, Calif: Botanica Press; 1992.
Hocking G. A Dictionary of Natural Products. Medford, NJ: Plexus; 1997.
Kinghorn A, Balandrin M, eds. Human Medicinal Agents from Plants. Washington, DC: American Chemical Society; 1993.
Magliulo E, Gagliardi B, Fiori GP. Results of a double blind study on the effect of silymarin in the treatment of acute viral hepatitis, carried out at two medical centres. Med Klinik. 1978;73:1060–1065.
Morazzoni P, Bombardelli E. Silybum marianum (Carduus marianus). Fitoterapia. 1995;LXVI.
Mourelle M, Favari L. Silymarin improves metabolism and disposition of aspirin in cirrhotic rats. Life Sci. 1988;43:201–207.
Murray M. The Healing Power of Herbs: The Enlightened Person’s Guide to the Wonders of Medicinal Plants. 2nd ed. Rocklin, Calif: Prima Publishing; 1995.
Murray M, Pizzorno J. Encyclopedia of Natural Medicine. 2nd ed. Rocklin, Calif: Prima Publishing; 1998.
Palasciano G, Portincasa P, Palmieri V, Ciani D, Vendemiale G, Altomare E. The effect of silymarin on plasma levels of malon-dialdehyde in patients receiving long-term treatment with psychotropic drugs. Curr Therapeut Res. 1994;55(5):537-545.
Schulz V, Hansel R, Tyler V. Rational Phytotherapy: A Physician’s Guide to Herbal Medicine. 3rd ed. Berlin, Germany: Springer-Verlag; 1998.
Tyler V. The Honest Herbal: A Sensible Guide to the Use of Herbs and Related Remedies. 3rd ed. New York, NY: Pharmaceutical Products Press; 1993:chap 3.
Valenzuela A, Lagos C, Schmidt K, et al. Silymarin protection against hepatic lipid peroxidation induced by acute ethanol intoxication in the rat. Biochem Pharmacol. 1985;34(12):2209–2212.
Zi X, Mukhtar H, Agarwal R. Novel cancer chemopreventive effects of a flavonoid antioxidant silymarin: inhibition of mRNA expression of an endogenous tumor promoter TNF-alpha. Biochem Biophys Res Commun. 1997;239(1):334–339.
von Schonfeld J, Weisbrod B, Muller MK. Silibinin, a plant extract with antioxidant and membrane stabilizing properties, protects exocrine pancreas from cyclosporin A toxicity. Cell Mol Life Sci. 1997;53(11–12):917–920.
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