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Milk Thistle


Laura Shane-McWhorter

, PharmD, University of Utah College of Pharmacy

Reviewed/Revised Jan 2022 | Modified Sep 2022

What is milk thistle?

What claims are made about milk thistle?

Does milk thistle work?

Well-designed scientific studies do not show that milk thistle significantly benefits people with a liver disorder or decreases death due to liver toxicity.

Some studies have found that milk thistle decreased fasting glucose and HbA1C, but it is not clear whether it is recommended for people who have diabetes or poor insulin sensitivity (prediabetes).

Milk thistle may decrease diabetes-related complications such as fatty liver and proteinuria. Milk thistle may also lower cholesterol. It is often combined with other supplements, such as berberine.

What are the possible side effects of milk thistle?

No serious side effects have been reported, although gastrointestinal upset may occur. Also, people who have allergies to chrysanthemums, marigolds, and daisies may also have allergic reactions to milk thistle.

What drug interactions occur with milk thistle?

Milk thistle may increase the effects of drugs that decrease blood sugar levels (hypoglycemic drugs) and may interfere with drugs used to treat human immunodeficiency virus (HIV) infection (such as indinavir or saquinavir). Milk thistle may increase the effects of warfarin, sometimes resulting in bleeding. Milk thistle may increase the blood levels of drugs that have certain chemical similarities (such as some chemotherapy drugs, calcium channel blockers, and some antibiotics).


There is no clear evidence to support the claims that milk thistle benefits people with a liver disorder, diabetes, prediabetes, any other disorder.

Milk thistle may lower blood sugar levels in people with type 2 diabetes; therefore, people with diabetes should consult their doctor before taking milk thistle. Pregnant women and women who have hormone-sensitive conditions should consult with their doctor before taking milk thistle.

Drugs Mentioned In This Article

Generic Name Select Brand Names
Milk Thistle XTRA
7T Gummy ES, Acephen, Aceta, Actamin, Adult Pain Relief, Anacin Aspirin Free, Aphen, Apra, Children's Acetaminophen, Children's Pain & Fever , Children's Pain Relief, Comtrex Sore Throat Relief, ED-APAP, ElixSure Fever/Pain, Feverall, Genapap, Genebs, Goody's Back & Body Pain, Infantaire, Infants' Acetaminophen, LIQUID PAIN RELIEF, Little Fevers, Little Remedies Infant Fever + Pain Reliever, Mapap, Mapap Arthritis Pain, Mapap Infants, Mapap Junior, M-PAP, Nortemp, Ofirmev, Pain & Fever , Pain and Fever , PAIN RELIEF , PAIN RELIEF Extra Strength, Panadol, PediaCare Children's Fever Reducer/Pain Reliever, PediaCare Children's Smooth Metls Fever Reducer/Pain Reliever, PediaCare Infant's Fever Reducer/Pain Reliever, Pediaphen, PHARBETOL, Plus PHARMA, Q-Pap, Q-Pap Extra Strength, Silapap, Triaminic Fever Reducer and Pain Reliever, Triaminic Infant Fever Reducer and Pain Reliever, Tylenol, Tylenol 8 Hour, Tylenol 8 Hour Arthritis Pain, Tylenol 8 Hour Muscle Aches & Pain, Tylenol Arthritis Pain, Tylenol Children's, Tylenol Children's Pain+Fever, Tylenol CrushableTablet, Tylenol Extra Strength, Tylenol Infants', Tylenol Infants Pain + Fever, Tylenol Junior Strength, Tylenol Pain + Fever, Tylenol Regular Strength, Tylenol Sore Throat, XS No Aspirin, XS Pain Reliever
Fortovase, Invirase
Coumadin, Jantoven
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