Interactions on record — worth a quick check against your medications. Based on 1 of 2 ingredients. Check your meds →
Dietary supplement

Milk Thistle Ingredients & Drug Interactions

by Nature's Answer

Milk Thistle label
See full label image
Capsule Category: Botanical
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Milk Thistle against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.

Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy

The interaction bottom line Most serious interaction: Moderate

Milk Thistle is a dietary supplement by Nature's Answer with 2 active ingredients. Its ingredients are commonly taken for liver health and protection, hepatitis, cirrhosis.Based on those ingredients, 954 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Milk Thistle. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Milk Thistle by Nature's Answer

Ask about any prescription or over-the-counter medication and we check it for interactions with Milk Thistle by Nature's Answer — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Milk Thistle by Nature's Answer

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Aug 20, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 2 of its 2 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains 2 active ingredients: milk thistle and milk thistle seed extract (silymarin). Both forms work to support liver function and overall health.

The capsules also contain inactive ingredients—rice flour, vegetable cellulose, and calcium silicate—which are fillers and binders that help hold the capsule together and ensure even distribution of the active ingredients.

Does it work?

Insufficient evidence
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed
Insufficient

There isn't enough reliable clinical evidence to rate this product's ingredients for its stated purpose.

Why this rating?
  • The label markets this product for: Promotes healthy liver function.
  • We looked for evidence on: Alcohol-related liver disease, Hepatitis B, Hepatitis C, Metabolic dysfunction-associated steatotic liver disease (MASLD), Nonalcoholic fatty liver disease (NAFLD), Nonalcoholic steatohepatitis (NASH) — and 4 related terms.
  • The closest evidence on file: Milk Thistle is rated "Insufficient Reliable Evidence To Rate" for Alcohol-related liver disease (Natural Medicines).
  • Also on file: Milk Thistle is rated "Insufficient Reliable Evidence To Rate" for Chemotherapy-induced hepatotoxicity, Metabolic dysfunction-associated steatotic liver disease (MASLD), Hepatitis C, Hepatitis B, and more.

The evidence for milk thistle in type 2 diabetes is rated possibly effective—clinical studies show it can lower blood sugar and HbA1c levels, even in people already on diabetes medication. For acne, alcohol-related liver disease, hay fever, gambling disorder, and Amanita mushroom poisoning, the evidence isn't established in the data we hold, so we can't say whether it works for those uses.

The evidence, ingredient by ingredient Milk Thistle

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 1 of the 1 matched ingredient.
  • Pregnancy & breastfeeding safety ratings cover 1 of 1.
  • General safety write-ups exist for 1 of 1.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Milk thistle is generally well tolerated in most adults. The most common side effects are mild stomach issues—bloating, diarrhea, indigestion, gas, and nausea—though these don't typically happen more often than with placebo.

Headache, dizziness, and sleep disturbances have also been reported. Rarely, allergic reactions including anaphylaxis have occurred.

The safety data advises against it during pregnancy because there isn't enough reliable information. During breastfeeding, safety isn't well studied, so caution is advised.

If you have a liver condition, a doctor should be involved in your care—quality and effectiveness can vary.

Side effects, ingredient by ingredient Milk Thistle

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 1 of the 1 matched ingredient can interact with medications — Milk Thistle.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; diabetes medications.
  • For scale: 955 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before taking this product, double-check with your doctor or pharmacist if you're on any antidiabetes drugs (insulin, metformin, sulfonylureas, or others)—milk thistle can increase low blood sugar risk. Blood thinners like warfarin need special attention too.

Also flag any hepatitis C drugs (especially ledipasvir or sofosbuvir), pain medications including morphine, transplant drugs like sirolimus, and any medications that depend on liver processing for clearance.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with insufficient evidence for its stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

Milk thistle may be worth considering if you have type 2 diabetes, but because it lowers blood sugar on its own, you'll need to work closely with your doctor or pharmacist if you're already on diabetes medication to avoid low blood sugar. If you take blood thinners, pain relievers, or hepatitis C or transplant drugs, check with your doctor or pharmacist before starting—the interactions are real and potentially serious.

Otherwise, it's generally well tolerated, but talk it over with them about whether it's right for you.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 2 of 2 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jan 7, 2019.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about Milk Thistle, straight from the product label.

Brand Nature's Answer
Barcode (UPC) 083000164163
Net contents 120 Vegetarian Capsule(s)
Market status On market
Date entered into DSLD Jan 7, 2019
DSLD ID 184934
Product type Botanical
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Vegan, Vegetarian, Adult (18 - 50 Years), Gluten Free
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Milk Thistle by Nature's Answer, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Capsule(s)
Maximum serving Sizes:
1 Capsule(s)
UPC/BARCODE
083000164163
IngredientAmount% DV
Milk Thistle20 mg--
Milk Thistle (Silybum marianum) seed extract175 mg--

Other ingredients: Rice Flour, Vegetable Cellulose, Calcium Silicate

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
Brand IP Statement(s)

Discover Nature's Answer and trust the Difference... The True Nature of Our Standards go way beyond the herb...

Discover Nature's Answer

2017 Nature's Answer

FDA Disclaimer Statement

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

Storage

Store in a cool, dry place.

Seals/Symbols

Gluten Free

General Statements

Since 1972 Promotes Healthy Liver Function

Formula

Minimum 140 mg Silymarin

FDA Statement of Identity

Dietary Supplement

Formulation

Vegan

Gluten-Free

Suggested/Recommended/Usage/Directions

Suggested Use: As a dietary supplement, take one (1) capsule three (3) times a day with food or water.

Precautions

Warning: Keep Out of Reach of Children.

Do not use if safety seal is damaged or missing.

If you are pregnant, nursing, taking any medications, planning any medical procedure or have a medical condition, consult with your healthcare practitioner before use.

General

18416 Rev. 1/18

Is this label outdated? Report a formula or label change and our pharmacy team will review it.

See for yourself

Milk Thistle by Nature's Answer label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

Milk Thistle label

Label images are published by the NIH Dietary Supplement Label Database for the version of this product on file. Always read your actual product label.

View the full label (PDF)
What’s inside

The Ingredients in Milk Thistle by Nature's Answer

These are the 2 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Capsule(s) Dosage formCapsule Amounts shown are per serving.

Most supplement products combine several ingredients, and a medication can interact with the product through any one of them. Each ingredient below shows whether it has known drug interactions.

Milk Thistle

Interacts with
954 drugs
20 mg per serving

Milk thistle is a popular herbal supplement most often used for liver health, and its main active component is a group of compounds called silymarin....

Milk Thistle monograph & interactions

Milk Thistle (Silybum marianum) seed extract

Interacts with
954 drugs
175 mg per serving Form: Silymarin

Milk thistle is a popular herbal supplement most often used for liver health, and its main active component is a group of compounds called silymarin....

Milk Thistle (Silybum marianum) seed extract monograph & interactions

Other (inactive) ingredients: Rice Flour, Vegetable Cellulose, Calcium Silicate. These complete the product’s ingredient list but are not active constituents.

Interaction report

Milk Thistle by Nature's Answer Drug Interactions

Want to check YOUR meds against Milk Thistle?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

 Go to the checker
954Drugs
254 Moderate 700 Minor

Ingredients driving the most interactions

Milk Thistle 954

Individual Drug Interactions

The ingredients in Milk Thistle interact with 954 drugs. Click any drug to see the details.

1 of the 2 ingredients in Milk Thistle interact with drugs. Each result below shows which ingredient is responsible. Milk Thistle

Each ingredient & the kinds of drugs it affects

For each ingredient in Milk Thistle with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.

Milk Thistle17 drug types · 954 drugs

Antidiabetes Drugs

Taking milk thistle with antidiabetes drugs may increase the risk of hypoglycemia.
Clinical research shows that milk thistle extract, alone or along with tree turmeric extract, can lower blood glucose levels and glycated hemoglobin (HbA1c) in patients with type 2 diabetes, including those already taking antidiabetes drugs. Additionally, animal research shows that milk thistle extract increases the metformin maximum plasma concentration and area under the curve and decreases the renal clearance of metformin, due to inhibition of the multi-drug and toxin extrusion protein 1 (MATE1) renal tubular transport protein.

Likelihood Possible Evidence B
Cytochrome P450 2B6 (Cyp2B6) Substrates

Theoretically, milk thistle might inhibit CYP2B6.
An in vitro study shows that silybin, a constituent of milk thistle, binds to and noncompetitively inhibits CYP2B6. Additionally, silybin might downregulate the expression of CYP2B6 by decreasing mRNA and protein levels.

Likelihood Possible Evidence D
Glucuronidated Drugs

Theoretically, milk thistle might affect the clearance of drugs that undergo glucuronidation.
Laboratory research shows that milk thistle constituents inhibit uridine diphosphoglucuronosyl transferase (UGT), the major phase 2 enzyme that is responsible for glucuronidation. Theoretically, this could decrease the clearance and increase levels of glucuronidated drugs. Other laboratory research suggests that a milk thistle extract of silymarin might inhibit beta-glucuronidase, although the significance of this effect is unclear.

Likelihood Possible Evidence D
Ledipasvir

Theoretically, milk thistle might increase the levels and clinical effects of ledipasvir.
Animal research in rats shows that milk thistle increases the area under the curve (AUC) for ledipasvir and slows its elimination.

Likelihood Possible Evidence D
Morphine

Theoretically, concomitant use of milk thistle with morphine might affect serum levels of morphine and either increase or decrease its effects.
Animal research shows that milk thistle reduces serum levels of morphine by up to 66%. In contrast, laboratory research shows that milk thistle constituents inhibit uridine diphosphoglucuronosyl transferase (UGT), the major phase 2 enzyme that is responsible for glucuronidation. Theoretically, this could decrease the clearance and increase morphine levels. The effect of taking milk thistle on morphine metabolism in humans is not known.

Likelihood Possible Evidence D
Raloxifene (Evista)

Theoretically, milk thistle might decrease the clearance and increase levels of raloxifene.
Laboratory research suggests that the milk thistle constituents silibinin and silymarin inhibit the glucuronidation of raloxifene in the intestines.

Likelihood Possible Evidence D
Sirolimus (Rapamune)

Milk thistle might decrease the clearance of sirolimus.
Pharmacokinetic research shows that a milk thistle extract of silymarin decreases the apparent clearance of sirolimus in hepatically impaired renal transplant patients. It is unclear if this interaction occurs in patients without hepatic impairment.

Likelihood Possible Evidence B
Sofosbuvir (Solvaldi)

Theoretically, milk thistle might decrease the levels and clinical effects of sofosbuvir.
Animal research in rats shows that milk thistle reduces the metabolism of sofosbuvir, as well as the hepatic uptake of its active metabolite.

Likelihood Possible Evidence D
Tamoxifen (Nolvadex)

Theoretically, the milk thistle constituent silibinin might increase tamoxifen levels and interfere with its conversion to an active metabolite.
Animal research suggests that the milk thistle constituent silibinin might increase plasma levels of tamoxifen and alter its conversion to an active metabolite. The mechanism appears to involve inhibition of pre-systemic metabolism of tamoxifen by cytochrome P450 (CYP) 2C9 and CYP3A4, and inhibition of P-glycoprotein-mediated efflux of tamoxifen into the intestine for excretion. Whether this interaction occurs in humans is not known.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Theoretically, milk thistle might increase the effects of warfarin.
In one case report, a man stabilized on warfarin experienced an increase in INR from 2.64 to 4.12 after taking a combination product containing milk thistle 200 mg daily, as well as dandelion, wild yam, niacinamide, and vitamin B12. Levels returned to normal after stopping the supplement. Although a direct correlation between milk thistle and the change in INR cannot be confirmed, some in vitro research suggests that milk thistle might inhibit cytochrome P450 2C9 (CYP2C9), an enzyme involved in the metabolism of various drugs, including warfarin.

Likelihood Possible Evidence D
Cytochrome P450 2C9 (Cyp2C9) Substrates

It is unclear if milk thistle inhibits CYP2C9; research is conflicting.
In vitro research suggests that milk thistle might inhibit CYP2C9. Additionally, 3 case reports from the World Health Organization (WHO) adverse drug reaction database describe increased toxicity in patients taking milk thistle and cancer medications that are CYP2C9 substrates, including imatinib and capecitabine. However, contradictory clinical research shows that milk thistle extract does not inhibit CYP2C9 or significantly affect levels of the CYP2C9 substrate tolbutamide. Differences in results could be due to differences in dosages or formulations utilized.

Likelihood Unlikely Evidence B
Cytochrome P450 3A4 (Cyp3A4) Substrates

It is unclear if milk thistle inhibits CYP3A4; research is conflicting.
While laboratory research shows conflicting results, pharmacokinetic research shows that taking milk thistle extract 420-1350 mg daily does not significantly affect the metabolism of the CYP3A4 substrates irinotecan, midazolam, or indinavir. However, 8 case reports from the World Health Organization (WHO) adverse drug reaction database describe increased toxicity in patients taking milk thistle and cancer medications that are CYP3A4 substrates, including gefitinib, sorafenib, doxorubicin, and vincristine.

Likelihood Unlikely Evidence D
Estrogens

Theoretically, milk thistle might interfere with estrogen therapy through competition for estrogen receptors.
Animal research suggests that a milk thistle extract of silymarin binds to estrogen receptor beta.

Likelihood Possible Evidence D
Hmg-Coa Reductase Inhibitors ("Statins")

Theoretically, milk thistle might interfere with statin therapy by decreasing the activity of organic anion transporting polypeptide 1B1 (OATB1B1) and inhibiting breast cancer resistance protein (BCRP).
Preliminary evidence suggests that a milk thistle extract of silymarin can decrease the activity of the OATP1B1, which transports HMG-CoA reductase inhibitors into the liver to their site of action, and animal research shows this increases the maximum plasma concentration of pitavastatin and pravastatin. The silibinin component also inhibits BCRP, which transports statins from the liver into the bile for excretion. However, in a preliminary study in healthy males, silymarin 140 mg three times daily had no effect on the pharmacokinetics of a single 10 mg dose of rosuvastatin.

Likelihood Unlikely Evidence D
Indinavir (Crixivan)

Theoretically, milk thistle may induce cytochrome P450 3A4 (CYP3A4) enzymes and increase the metabolism of indinavir; however, results are conflicting.
One pharmacokinetic study shows that taking milk thistle (Standardized Milk Thistle, General Nutrition Corp.) 175 mg three times daily in combination with multiple doses of indinavir 800 mg every 8 hours decreases the mean trough levels of indinavir by 25%. However, results from the same pharmacokinetic study show that milk thistle does not affect the overall exposure to indinavir. Furthermore, two other pharmacokinetic studies show that taking specific milk thistle extract (Legalon, Rottapharm Madaus; Thisilyn, Nature's Way) 160-450 mg every 8 hours in combination with multiple doses of indinavir 800 mg every 8 hours does not reduce levels of indinavir.

Likelihood Unlikely Evidence B
Organic Anion-Transporting Polypeptide Substrates (Oatp)

Milk thistle may inhibit one form of OATP, OATP-B1, which could reduce the bioavailability and clinical effects of OATP-B1 substrates.
In vitro research shows that milk thistle inhibits OATP-B1. Two case reports from the World Health Organization (WHO) adverse drug reaction database describe increased toxicity in patients taking milk thistle and cancer medications that are OATP substrates, including sorafenib and methotrexate. OATPs are expressed in the small intestine and liver and are responsible for the uptake of drugs and other compounds into the body. Inhibition of OATP may reduce the bioavailability of oral drugs that are substrates of OATP.

Likelihood Possible Evidence D
P-Glycoprotein Substrates

Theoretically, milk thistle might increase the absorption of P-glycoprotein substrates. However, this effect does not seem to be clinically significant.
In vitro research shows that milk thistle can inhibit P-glycoprotein activity and 1 case report from the World Health Organization (WHO) adverse drug reaction database describes increased abdominal pain in a patient taking milk thistle and the cancer medication vincristine, a P-glycoprotein substrate, though this patient was also taking methotrexate. However, a small pharmacokinetic study in healthy volunteers shows that taking milk thistle (Enzymatic Therapy Inc.) 900 mg, standardized to 80% silymarin, in 3 divided doses daily for 14 days does not affect absorption of digoxin, a P-glycoprotein substrate.

Likelihood Unlikely Evidence B
Milk Thistle full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Milk Thistle, from the product label.

Nature's Answer

See all Nature's Answer products
Name
Nature's Answer
Street Address
85 Commerce Drive
City
Hauppauge
State
NY
ZipCode
11788
Phone Number
(800) 439-2324
Web Address
www.naturesanswer.com
Pharmacist Counseling Corner

Milk Thistle by Nature's Answer: Common Questions

Does Milk Thistle by Nature's Answer interact with any medications?
Yes. Based on its ingredients, Milk Thistle has a known interaction with 954 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Milk Thistle contains 2 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Can I take this if I'm on diabetes medication?
Not without checking first. Milk thistle lowers blood sugar on its own, and clinical studies show it does so even in people already taking diabetes drugs. Combined, the risk of blood sugar dropping too low jumps. Talk to your doctor or pharmacist—you may need dose adjustments or closer monitoring.
Is it safe during pregnancy?
No. There isn't enough reliable safety information, so the safety data advises against it during pregnancy. If you're pregnant or planning to be, talk with your doctor or pharmacist before taking it.
What are the most common side effects?
Mild stomach issues—bloating, diarrhea, indigestion, gas, and nausea. The data shows these don't typically happen more often than with placebo. Headache, dizziness, and sleep problems have been reported too. Serious allergic reactions are rare but possible.
Does milk thistle work for liver health?
The evidence we have establishes that it's possibly effective for type 2 diabetes. For alcohol-related liver disease and other liver conditions, the evidence isn't established in our data, so we can't say whether it helps. If you have liver disease, involve your doctor in your care.
Is it safe while breastfeeding?
Safety during breastfeeding isn't well studied, so caution is advised. Talk with your doctor or pharmacist to weigh the benefits and risks for your situation.
What's the difference between the two ingredients in this product?
Both are milk thistle—one is the whole seed, the other is a concentrated seed extract (silymarin). They work the same way and have the same interactions with medications, so from a safety and effectiveness standpoint, they're the same active ingredient listed twice.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

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Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

Milk Thistle label
Go deeper

The Full Monographs Behind Milk Thistle’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Herb & supplement monograph

Milk Thistle

Interacts with 954 drugs

Milk thistle is a popular herbal supplement most often used for liver health, and its main active component is a group of compounds called silymarin. While it is generally well tolerated, th...

Read the full Milk Thistle monograph →
Sources

Sources & How We Checked

Milk Thistle's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

The 69 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

Milk Thistle 69 references
  1. Ferenci P, Dragosics B, Dittrich H, et al. Randomized controlled trial of silymarin treatment in patients with cirrhosis of the liver. J Hepatol 1989;9:105-13. PubMed
  2. Anon. Milk thistle: Effects on liver disease and cirrhosis and clinical adverse effects. Summary, Evidence Report/Technology Assessment: Number 21, September 2000. Agency for Healthcare Research and Quality, Rockville, MD. Available at: http://www.ahrq.g
  3. Beckmann-Knopp S, Rietbrock S, Weyhenmeyer R, et al. Inhibitory effects of silibinin on cytochrome P-450 enzymes in human liver microsomes. Pharmacol Toxicol 2000;86:250-6. PubMed
  4. Venkataramanan R, Ramachandran V, Komoroski BJ, et al. Milk thistle, a herbal supplement, decreases the activity of CYP3A4 and uridine diphosphoglucuronosyl transferase in human hepatocyte cultures. Drug Metab Dispos 2000;28:1270-3. DOI
  5. Kim DH, Jin YH, Park JB, Kobashi K. Silymarin and its components are inhibitors of beta-glucuronidase. Biol Pharm Bull 1994;17:443-5. PubMed
  6. 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;28:615-21. PubMed
  7. Piscitelli SC, Formentini E, Burstein AH, et al. Effect of milk thistle on the pharmacokinetics of indinavir in healthy volunteers. Pharmacotherapy 2002;22:551-6. PubMed
  8. Boerth J, Strong KM. The clinical utility of milk thistle (Silybum marianum) in cirrhosis of the liver. J Herb Pharmacother 2002;2:11-7.
  9. Tanamly MD, Tadros F, Labeeb S, et al. Randomised double-blinded trial evaluating silymarin for chronic hepatitis C in an Egyptian village: study description and 12-month results. Dig Liver Dis 2004;36:752-9. PubMed
  10. Gurley BJ, Gardner SF, Hubbard MA, et al. In vivo assessment of botanical supplementation on human cytochrome P450 phenotypes: Citrus aurantium, Echinacea purpurea, milk thistle, and saw palmetto. Clin Pharmacol Ther 2004;76:428-40. .
  11. Huseini HF, Larijani B, Heshmat R, et al. The efficacy of Silybum marianum (L.) Gaertn. (silymarin) in the treatment of type II diabetes: a randomized, double-blind, placebo-controlled, clinical trial. Phytother Res 2006;20;1036-9.
  12. Deng JW, Shon JH, Shin HJ, et al. Effect of silymarin supplement on the pharmacokinetics of rosuvastatin. Pharm Res 2008;25:1807-14. PubMed
  13. Kim CS, Choi SJ, Park CY, et al. Effects of silybinin on the pharmacokinetics of tamoxifen and its active metabolite, 4-hydroxytamoxifen in rats. Anticancer Res 2010;30:79-85.
  14. Sridar C, Goosen TC, Kent UM, et al. Silybin inactivates cytochromes P450 3A4 and 2C9 and inhibits major hepatic glucuronosyltransferases. Drug Metab Dispos 2004;32:587-94. PubMed
  15. van Erp NP, Baker SD, Zhao M, et al. Effect of milk thistle (Silybum marianum) on the pharmacokinetics of irinotecan. Clin Cancer Res 2005;11:7800-6.
  16. Budzinski JW, Trudeau VL, Drouin CE, et al. Modulation of human cytochrome P450 3A4 (CYP3A4) and P-glycoprotein (P-gp) in Caco-2 cell monolayers by selected commercial-source milk thistle and goldenseal products. Can J Physiol Pharmacol 2007;85:966-78.
  17. Doehmer J, Weiss G, McGregor GP, Appel K. Assessment of a dry extract from milk thistle (Silybum marianum) for interference with human liver cytochrome-P450 activities. Toxicol In Vitro 2011;25:21-7. PubMed
  18. Jiao Z, Shi XJ, Li ZD, et al. Population pharmacokinetics of sirolimus in de novo Chinese adult renal transplant patients. Br.J.Clin.Pharmacol. 2009;68(1):47-60.
  19. Gurley, B. J., Barone, G. W., Williams, D. K., Carrier, J., Breen, P., Yates, C. R., Song, P. F., Hubbard, M. A., Tong, Y., and Cheboyina, S. Effect of milk thistle (Silybum marianum) and black cohosh (Cimicifuga racemosa) supplementation on digoxin phar
  20. Allain, H., Schuck, S., Lebreton, S., Strenge-Hesse, A., Braun, W., Gandon, J. M., and Brissot, P. Aminotransferase levels and silymarin in de novo tacrine-treated patients with Alzheimer's disease. Dement.Geriatr.Cogn Disord. 1999;10(3):181-185. PubMed
  21. Angulo, P., Patel, T., Jorgensen, R. A., Therneau, T. M., and Lindor, K. D. Silymarin in the treatment of patients with primary biliary cirrhosis with a suboptimal response to ursodeoxycholic acid. Hepatology 2000;32(5):897-900. PubMed
  22. Bean, P. The use of alternative medicine in the treatment of hepatitis C. Am.Clin.Lab 2002;21(4):19-21.
  23. Hussain, S. A. Silymarin as an adjunct to glibenclamide therapy improves long-term and postprandial glycemic control and body mass index in type 2 diabetes. J.Med.Food 2007;10(3):543-547. PubMed
  24. El-Kamary, S. S., Shardell, M. D., Abdel-Hamid, M., Ismail, S., El-Ateek, M., Metwally, M., Mikhail, N., Hashem, M., Mousa, A., Aboul-Fotouh, A., El-Kassas, M., Esmat, G., and Strickland, G. T. A randomized controlled trial to assess the safety and effic
  25. Gharagozloo, M., Moayedi, B., Zakerinia, M., Hamidi, M., Karimi, M., Maracy, M., and Amirghofran, Z. Combined therapy of silymarin and desferrioxamine in patients with beta-thalassemia major: a randomized double-blind clinical trial. Fundam.Clin.Pharmaco
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DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

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