Milk Thistle

Plant Part Used



While milk thistle has a number of historical uses, current research has primarily focused on milk thistle’s ability to support healthy liver function. A standardized extract is derived from the seed of the plant.

Interactions and Depletions


Dosage Info

Dosage Range

80-200 mg (standardized extract), 1-3 times daily.

Tea: 2 to 3 cups daily using ½ teaspoon of herb per cup. (1)

Most Common Dosage

80 mg (standardized extract), 3 times a day.

Tea: 2 cups daily using ½ teaspoon of herb per cup.


[span class=doc]Standardization represents the complete body of information and controls that serve to enhance the batch to batch consistency of a botanical product, including but not limited to the presence of a marker compound at a defined level or within a defined range.[/span]

The most current available medical and scientific literature indicates that this dietary supplement should be standardized to 80% silymarin per dose.

Reported Uses

There are three active components in milk thistle, all of which may work to protect the liver. Because of these benefits, it has been used in the treatment of a variety of liver disorders including chemical-induced liver damage and hepatitis. (2) , (3) One laboratory experiment indicated that one of the active ingredients in milk thistle, silibinin, may help decrease the impact of the negative effects on kidney cells damaged by paracetamol, cisplatin, and vincristin. (4)

Milk thistle has also been used to treat gallbladder dysfunctions and psoriasis. Other studies have pointed to milk thistle’s support of liver health in alcoholics and for those experiencing side effects from psychotropic drugs. (5) , (6) Milk thistle may also increase the effectiveness of the antioxidant, glutathione in the liver. (7)

One of milk thistle’s more celebrated uses is as an antidote to the death cup mushroom. It is claimed to be 100 percent effective in preventing harm from ingesting the deadly mushroom. (8) A standardized milk thistle product was recently reported to protect the liver from damage associated with acetaminophen overdoses. (9) , (10)

Toxicities & Precautions


[span class=alert]Be sure to tell your pharmacist, doctor, or other health care providers about any dietary supplements you are taking. There may be a potential for interactions or side effects.[/span]


This dietary supplement is considered safe when used in accordance with proper dosing guidelines.

Side Effects

Side effects are possible with any dietary supplement. This dietary supplement may cause loose stools or aggravation of hemorrhoidal veins with extended use. Tell your doctor if these side effects become severe or do not go away.

Pregnancy/ Breast Feeding

To date, the medical literature has not reported any adverse effects related to fetal development during pregnancy or to infants who are breast-fed. Yet little is known about the use of this dietary supplement while pregnant or breast-feeding. Therefore, it is recommended that you inform your healthcare practitioner of any dietary supplements you are using while pregnant or breast-feeding.

Age Limitations

This supplement should not be used in children unless recommended by your physician.


  1. PDR for Herbal Medicines, 2nd edition. Montvale, NJ: Medical Economics Company; 2000:518.
  2. Schopen RD, et al. Therapy of Hepatoses. Therapeutic Use of Silymarin. Med Welt. 1969;21:691-98.
  3. Valenzuela A, et al. Silymarin Protection Against Hepatic Lipid Peroxidation Induced by Acute Ethanol Intoxication in the Rat. Biochem Pharm. 1985;34:2209-12.
  4. View Abstract: Sonnenbichler J, Scalera F, Sonnenbichler I, et al. Stimulatory Effects of Silibinin and Silicristin from the Milk Thistle Silybum marianum on Kidney Cells. J Pharmacol Exp Ther. Sep1999;290(3):1375-83.
  5. View Abstract: Varga M, et al. Ethanol Elimination in Man Under Influence of Hepatoprotective Silibinin. Blutalkohol. Nov1991;28(6):405-08.
  6. Carrescia O, et al. Silymarin in the Prevention of Hepatic Damage by Psychopharmacologic Drugs. Experimental Premises and Clinical Evaluations. Clin Ter. 1980;95(2):157-64.
  7. View Abstract: Valenzuela A, et al. Selectivity of Silymarin on the Increase of the Glutathione Content in Different Tissues of the Rat. Planta Medica. 1989;55:1550-52.
  8. View Abstract: Vogel G, et al. Protection by Silibinin Against Amanita Phalloides Intoxication in Beagles. Toxicol Appl Pharm. 1984;73:355-62.
  9. Dehpour AR, et al. Liquorice Components Protect Liver Damage Induced by Actaminophen. Poster Presentation, 48th Annual Meeting of the International Congress of the Society of Medicinal Plant Research, P2A/23. Sep2000.
  10. View Abstract: Shear NH, Malkiewicz IM, Klein D, et al. Acetaminophen-induced Toxicity to Human Epidermoid Cell Line A431 and Hepatoblastoma Cell Line Hep G2, In Vitro, is Diminished by Silymarin. Skin Pharmacol. 1995;8(6):279-91.






in this scope
Malaysian Herbal Monograph​
Medicinal Herbs & Plants Monographs​
Traditional Chinese Medicine Herbs (Professional Data)
Herbal Medicines Compendium (HMC) - U.S​