Drug & supplement interaction

Milk Thistle + Rosuvastatin

Rosuvastatin brand names: Crestor, Ezallor.

Minor Interaction
The bottom line Minor

Milk Thistle has a minor interaction with Rosuvastatin. 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).

Read the full interaction report
SeverityMinor
LikelihoodUnlikely
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Milk Thistle and Rosuvastatin

Here is the interaction we found between these two, with the evidence behind it.

Minor

HMG-CoA REDUCTASE INHIBITORS ("Statins")

Why this applies to Rosuvastatin

Rosuvastatin falls under HMG-CoA REDUCTASE INHIBITORS ("Statins") — the group Milk Thistle interacts with.

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.
Severity Minor Likelihood Unlikely Evidence D

Interaction has been demonstrated in animal or in lab research but has been shown not to occur in humans..

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the honest picture with milk thistle and rosuvastatin (Crestor, Ezallor). In a test tube, silymarin (milk thistle's active part) can slow the transporters that move statins into the liver and out into bile. In theory, that could let a little more rosuvastatin linger in your blood. If that happened, you might be slightly more prone to typical statin side effects like muscle aches or soreness.

But here's the reassuring part: in a small study of healthy men, milk thistle did not change rosuvastatin levels at all. So this is mostly a lab and animal concern, not something that has shown up in real people. The risk is rated minor and unlikely. Still, if you take both and notice new muscle pain or weakness, let your pharmacist or doctor know before changing anything.

References
  1. Deng JW, Shon JH, Shin HJ, et al. Effect of silymarin supplement on the pharmacokinetics of rosuvastatin. Pharm Res 2008;25:1807-14. PubMed
  2. Bechtold BJ, Lynch KD, Oyanna VO, et al. Rifampin- and Silymarin-Mediated Pharmacokinetic Interactions of Exogenous and Endogenous Substrates in a Transgenic OATP1B Mouse Model. Mol Pharm 2024;21(5):2284-2297. PubMed

What These Ratings Mean

Every interaction above is graded three ways — here’s the key to each label.

Severity how clinically significant the interaction is
Major

Clinically significant. Avoid the combination, or use only under close professional supervision.

Moderate

Usually worth avoiding or managing — may need monitoring, a dose change, or timing apart.

Minor

Generally not serious. Be aware of it and mention it to your pharmacist.

Likelihood how strong the evidence is that the interaction actually happens in people
  • LikelyWell-controlled human studies have demonstrated the likely existence of this interaction.
  • ProbableInteraction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.
  • PossibleInteraction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.
  • UnlikelyInteraction has been demonstrated in animal or in lab research but has been shown not to occur in humans.
Evidence the quality of the studies behind the rating (graded A–D)
  • AHigh-quality meta-analysis (quantitative systematic review).
  • BCase-control study.
  • CConsensus.
  • DAnecdotal evidence.

These ratings are for information only. Never start, stop, or otherwise change your therapy before speaking with your provider.

Keep it in perspective

Milk Thistle Also Interacts With Other Medications

Milk Thistle has 254 moderate, 699 minor known drug interactions in our database — the Rosuvastatin one above is one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Milk Thistle

Covers the 2,830 medications we’ve checked against Milk Thistle. Pick one to open its full report.

From our Q&A

Questions About Milk Thistle or Rosuvastatin

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Milk Thistle or Rosuvastatin, not necessarily both, but if one is close to what you were about to ask it will usually go further than a database entry can:

Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.

Everything else you take

See Every Supplement That Interacts With Rosuvastatin

This page covers Milk Thistle only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Rosuvastatin page lists 63 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Beer (major), Grapefruit (major), Siberian Cocklebur (major) and Wine (major).

By severity: 5 major · 48 moderate · 10 minor.

From our pharmacist’s overview on the Rosuvastatin page

“Rosuvastatin (Crestor, Ezallor) is a statin taken daily for years to lower cholesterol, and its supplement list deserves real scrutiny, not a quick skim. Five of the 63 ingredients on file carry a major rating, headed by grapefruit, which can raise statin blood levels, and by heavy drinking, since beer and wine compound the strain this…”

Reviewed by 2 · Jul 18, 2026

Open the Rosuvastatin interaction page

One more smart check

Taking Milk Thistle as Part of a Dietary Supplement Product? Check It for Interactions

We hold 4,560 real supplement products containing Milk Thistle, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Milk Thistle. Your product may carry other ingredients that interact with Rosuvastatin too, on top of Milk Thistle — and those would not show on this page. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Milk Thistle and Rosuvastatin Sit Against Everything Else

Out of every supplement and medication people look up on HelloPharmacist, here is where these two land this week — and which way each has been moving.

Supplement Milk Thistle
Top 5%

#49 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Rosuvastatin
Top 1%

#20 of 2,830 medications looked up here in the last 7 days

29 days ago today

Position among everything looked up on this site, not a measure of how commonly either one is used or how important it is. A supplement can climb this list because of a news story. It counts every request to the page, automated ones included, and nothing here identifies anyone.

Supplement

About Milk Thistle

What is Milk Thistle?

Milk Thistle
  • Liver health and protection
  • Hepatitis
  • Cirrhosis
  • Gallbladder problems
  • High cholesterol
  • Type 2 diabetes support

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, the scientific evidence that it meaningfully improves liver disease or other conditions is mixed and far from conclusive. Talk with your pharmacist or doctor before using it, especially if you have a liver condition or take other medicines.

Read the full Milk Thistle monograph & all interactions
Medication

About Rosuvastatin

What Is Rosuvastatin Used For?

Brand names: Crestor, Ezallor

Rosuvastatin tablets are used alongside diet changes to lower LDL-C ("bad" cholesterol), total cholesterol, and triglycerides (blood fats), and to raise HDL-C ("good" cholesterol) in adults with high cholesterol or mixed cholesterol problems. They are also used in adults with very high triglycerides, a condition called primary dysbetalipoproteinemia (Type III, a genetic fat-metabolism disorder), and to slow the buildup of plaque in arteries (atherosclerosis).

In people without established heart disease but with multiple risk factors, rosuvastatin tablets can reduce the risk of heart attack, stroke, and procedures to open blocked arteries. For children and teens aged 8 and older with heterozygous familial hypercholesterolemia (HeFH, an inherited high-cholesterol condition), the tablet form is used to lower LDL-C after diet alone has not worked. Crestor tablets are also approved to treat homozygous familial hypercholesterolemia (HoFH, a more severe inherited form) in adults and in children aged 7 and older.

See full Rosuvastatin drug information
Keep checking

Other Drugs & Milk Thistle

Browse every other medication we’ve checked against Milk Thistle — both the ones with a known interaction and the ones without. Select any drug for the full detail.

0Major
254Moderate
699Minor
1,876No known interaction
Moderate

254 interactions

Showing 60 of 254 moderate interactions — see all 254 on the Milk Thistle page.

Minor

699 interactions

Showing 60 of 699 minor interactions — see all 699 on the Milk Thistle page.

No interaction 1,876 drugs checked — show the list
Sources

Sources & How We Checked

Interaction details are evidence-graded and sourced from the Natural Medicines database. The medication overview comes from MedlinePlus.

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

Parts of this content are provided by the Therapeutic Research Center, LLC.

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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Pharmacist Counseling Corner

Taking Milk Thistle and Rosuvastatin Together: Common Questions

Can you take Milk Thistle with Rosuvastatin?
There is only a minor interaction, which is usually not serious. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Milk Thistle and Rosuvastatin interaction?
We rate it Minor. This interaction is generally not clinically significant, but it remains worth noting and discussing with your pharmacist.

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

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This information is for education only and is not a substitute for professional medical advice. Always check with your pharmacist or doctor before starting, stopping, or combining supplements and medications.