Milk Thistle (Silybum marianum
Be aware that the U. S. Food and Drug Administration does not strictly
regulate herbs and dietary supplements. There is no guarantee of strength,
purity or safety of products containing or claiming to contain valerian.
Decisions to use herbs or supplements should be carefully considered. Individuals
using prescription drugs should discuss taking herbs or supplements with
their pharmacists or health care providers before starting.
Scientists have studied milk thistle for the following health problems:
Cirrhosis (liver disease)
Multiple studies from Europe suggest that milk thistle may improve cirrhosis
and lengthen the lives of cirrhosis patients. However, most of these studies
are poorly designed. Better-quality research is needed before a strong
recommendation can be made.
Hepatitis (liver inflammation)
Multiple studies of milk thistle for chronic hepatitis caused by viruses
or alcohol report improvements in liver tests. However, most of these studies
are small and poorly designed. Better research is needed before a strong
recommendation can be made.
Studies of milk thistle for acute viral hepatitis do not provide clear results.
Therefore, milk thistle cannot be recommended for this potentially
Liver damage caused by toxins
There are studies of milk thistle to treat or prevent liver damage caused
by drugs or toxic chemicals. Results of this research are unclear. Therefore,
there is not enough scientific evidence to recommend milk thistle for this
Laboratory and animal studies show that milk thistle may lower cholesterol.
However, there are only a few studies in humans in this area, with unclear
results. Therefore, there is not enough scientific evidence to recommend
milk thistle for this use.
Type 2 diabetes (adult-onset diabetes)
Studies in humans of milk thistle for diabetes are low quality. Therefore,
it cannot be recommended at this time.
Amanita phalloides mushroom poisoning
Several natural medicine textbooks support the use of milk thistle for
Amanita phalloides mushroom poisoning, based on tradition and expert
opinion. Over the past 30 years, animal research and poor-quality studies
in humans have reported benefits. However, without better-quality scientific
evidence, it is unclear if milk thistle is useful for mushroom poisoning.
There is ongoing laboratory research of the anticancer effects of milk thistle
for breast, cervical and prostate cancer. At this time, there are not enough
studies in humans to recommend milk thistle for these diseases.
Milk thistle has been suggested for many other uses, based on tradition
or on scientific theories. However, these uses have not been thoroughly studied
in humans, and there is limited scientific evidence about safety or
effectiveness. Some of these suggested uses are for conditions that are
potentially very serious and even life-threatening. You should consult a
health care provider before using milk thistle for any unproven use.
|Acute liver injury
Amiodarone toxicity reactions
Breast milk stimulation
Chronic liver injury
Diabetic nerve pain
Hepatitis C virus
Primary biliary cirrhosis
Solar ultraviolet protection
People with allergies to plants in the aster family (Compositea,
Asteraceae) or to the common thistle or any of its constituents (silybin,
silychristin, silydianin, silymonin, siliandrin) may have allergic reactions
to milk thistle. Anaphylactic shock (a severe allergic reaction) from milk
thistle tea occurred in one person who also had a kiwi fruit allergy.
Studies report that milk thistle is well tolerated in recommended doses.
Some people experience stomach upset. There are rare reports of rashes,
headaches, heartburn, joint pain and impotence with milk thistle use. One
person experienced sweating, nausea, stomach pain, diarrhea, vomiting, weakness
and collapse after taking milk thistle. She improved after 24 hours. High
liver enzyme levels in one person taking milk thistle returned to normal
after the person stopped taking the herb.
Pregnancy And Breast-Feeding
Milk thistle is sometimes recommended by herbalists to improve the flow of
breast milk in nursing mothers. Two very short studies of milk thistle use
by pregnant women report no side effects. However, there is not enough scientific
evidence at this time to support the use of milk thistle during pregnancy
Interactions with drugs, supplements and other herbs have not been thoroughly
studied. The interactions listed below have been reported in scientific
publications. If you are taking prescription drugs, speak with your health
care provider or pharmacist before using herbs or dietary supplements.
Interactions With Drugs
Additive anticancer effects may occur with milk thistle and chemotherapy
drugs such as doxorubicin, cisplatin and carboplatin. Check with your oncologist
and pharmacist before taking milk thistle. Animal studies suggest that milk
thistle may interfere with the way the liver processes certain drugs. As
a result, milk thistle may cause the levels of drugs in the body to be too
high, leading to serious side effects. Some studies suggest that indinavir
levels may be altered, but other study results disagree. Milk thistle may
lower blood sugar levels, and patients taking oral drugs for diabetes or
using insulin should be monitored closely by their health care provider while
using milk thistle. Dosing adjustments may be necessary. A possible interaction
with phenytoin (Dilantin) has been reported with milk thistle. However, the
facts are unclear. Milk thistle ingredients have been shown to prevent amiodarone
toxicity in studies done in animals, but before this herb is used for this
indication, further studies in humans must be done.
Interactions With Herbs And Dietary Supplements
Milk thistle may lower blood sugar levels. People using other herbs or
supplements that may affect blood sugar levels, such as
melon (Momordica charantia), should be monitored closely by their
health care provider while using milk thistle. Dosing adjustments may be
Silymarin and vitamin E have been shown to prevent amiodarone toxicity in
studies done in animals, but before this herb is used for this indication,
further studies in humans must be done. Milk thistle may bind with iron and
slow calcium metabolism.
The doses listed below are based on scientific research, publications
or traditional use. Because most herbs and supplements have not been thoroughly
studied or monitored, safety and effectiveness may not be proven. Brands
may be made differently, with variable ingredients even within the same brand.
Combination products often contain small amounts of each ingredient and may
not be effective. Appropriate dosing should be discussed with your health
care provider before starting therapy; always read the recommendations on
a product's label. The dosing for unproven uses should be approached cautiously,
because scientific information is limited in these areas.
Note: One study analyzing the stability of milk thistle tincture showed
a shelf life of only about three months.
For Liver Diseases Adults (Aged
18 Or Older)
Capsules: Doses ranging from 160 to 800 milligrams daily by mouth
have been used for cirrhosis, hepatitis and toxic liver damage. Capsules
should contain 70 percent to 80 percent of the chemical silymarin. Consult
your health care provider to determine the dose that is right for you.
For Other Conditions
The safety and effectiveness of doses for other conditions are not clear.
Milk thistle has also been used intravenously, but this method of administration
has not been proven safe. Milk thistle does not dissolve easily in water,
therefore milk thistle tea is not recommended.
Children (Younger Than 18): There is not enough scientific evidence
to recommend using milk thistle for children.
Although milk thistle has been suggested for many conditions, the most promising
uses supported by science are the treatment of cirrhosis and hepatitis. Evidence
does not support the use of milk thistle for other health problems. Check
with your health care provider or pharmacist before taking milk thistle if
you are taking other drugs, herbs or supplements, because there may be dangerous
interactions. Diabetic patients should monitor their blood sugar levels closely.
Consult your health care provider immediately if you experience side effects.
The information in this monograph was prepared by the professional staff
at Natural Standard, based on thorough systematic review of scientific evidence.
The material was reviewed by the Faculty of the Harvard Medical School with
final editing approved by Natural Standard.
Standard: An organization that produces scientifically based reviews
of complementary and alternative medicine (CAM) topics
for Complementary and Alternative Medicine (NCCAM): A division of the
U.S. Department of Health & Human Services dedicated to research
Selected Scientific Studies: Milk Thistle
Natural Standard reviewed more than 265 articles to prepare the professional
monograph from which this version was created.
Some of the more recent studies are listed below:
Agoston M, Orsi F, Feher E, et al. Silymarin and vitamin E reduce
amiodarone-induced lysosomal phospholipidosis in rats. Toxicology 2003;Aug
Bass NM. Is there any use for nontraditional or alternative therapies in
patients with chronic liver disease? Curr Gastroenterol Rep 1999;Feb-Mar,
Bean P. The use of alternative medicine in the treatment of hepatitis C.
Am Clin Lab 2002;May, 21(4):19-21.
DiCenzo R, Shelton M, Jordan K, et al. Coadministration of milk thistle and
indinavir in healthy subjects. Pharmacotherapy 2003;Jul, 23(7):866-870.
Ferenci P, Dragosics B, Dittrich H, et al. Randomized controlled trial of
silymarin treatment in patients with cirrhosis of the liver. J Hepatol 1989;Jul,
Flora K, Hahn M, Rosen H, et al. Milk thistle (Silybum marianum) for
the therapy of liver disease. Am J Gastroenterol 1998;93(2):139-143.
Jacobs BP, Dennehy C, Ramirez G, et al. Milk thistle for the treatment of
liver disease: a systematic review and meta-analysis. Am J Med 2002;Oct 15,
Marcelli R, Bizzoni P, Conte D, et al. Randomized controlled study of the
efficacy and tolerability of a short course of IdB 1016 in the treatment
of chronic persistent hepatitis. Eur Bull Drug Res 1992;1(3):131-135.
Mulrow C, Lawrence V, Jacobs B, et al. Milk thistle: effects on liver disease
and cirrhosis and clinical adverse effects. Evid Rep Technol Assess (Summ)
Pares A, Planas R, Torres M, et al. Effects of silymarin in alcoholic patients
with cirrhosis of the liver: results of a controlled, double-blind, randomized
and multicenter trial. J Hepatol 1998;28(4):615-621.
Singh RP, Agarwal R. Prostate cancer prevention by silibinin. Curr Cancer
Drug Targets 2004 Feb;4(1):1-11.
Velussi M, Cernigoi AM, De Monte A, et al. Long-term (12 months) treatment
with an anti-oxidant drug (silymarin) is effective on hyperinsulinemia, exogenous
insulin need and malondialdehyde levels in cirrhotic diabetic patients. J
Zuber R, Modriansky M, Dvorak Z, et al. Effect of silybin and its congeners
on human liver microsomal cytochrome P450 activities. Phytother Res 2002;Nov,
Last updated July 14, 2005