Milk Thistle: The Liver Cleanser?

HEALTH TALK

Admiral butterfly on milk thisle (Photo – pixabay.com).

The seeds from Silybum marianum are used to formulate Milk thistle preparations.

By H. S. Nemr

Source and chemical components

This plant is native to the Mediterranean area but is also found in Europe and North America.

Milk thistle contains Silymarin which consists of three flavono-lignan compounds (Silybinin, Silydyanin, and Silychristin).

Actions

Silymarin exerts anti-hepatotoxic and hepatoprotective actions against hepato-toxins. It alters the outer liver membrane cell structure so that toxins cannot enter the hepatic cell. It also stimulates RNA polymerase A which enhances ribosome protein synthesis and leads to activation of the regenerative capacity of the liver through cell development.

Silybum marianum fruits (Photo – en.wikipedia.org).

Therapeutic and reported folk uses

Milk thistle preparations are believed to be useful as “liver cleansing” agents. The extract has been used as an antidote for accidental ingestion of poisonous mushrooms. In patients with psychotropic medication induced liver dysfunction, Milk thistle improved the liver function laboratory results.

The German Federal Institute for Drugs and Medical Devices approves the use of Milk thistle for toxic liver and as a supportive treatment for chronic inflammatory liver disease.

Several studies have confirmed the therapeutic role of Silymarin in hepatic dysfunction; however, the limitations in these trials included flaws in the study design and inconsistency of the measuring parameters.

Dosage

Oral: 80-200 mg 1-3 times /day, standardized to contain 80% silymarin per dose; up to 800 mg/day has been studied.

Interactions

Milk thistle may inhibit the drug metabolism of Antidiabetics agents, Insulin, cytochrome P450 substrates, Glucuronidated agents (ex: Lorazepam, Lamotrigine, Entacapone), Indinavir, Estrogens, and Antilipemic agents.

Adverse reactions and precautions

GI: Mild laxative effect.
GU: Menstrual and uterine stimulation.
Milk thistle is contraindicated in pregnant and breastfeeding females.

H.S. Nemr is a graduate of BAU pharmacy school. He is currently a medication safety officer at Johns Hopkins Aramco Healthcare system.

References

1. Professional’s Handbook of Complementary Alternative Medicines, Springhouse, 2nd edition.\
2. Lexicomp’s Natural Products Database.