Drug & supplement interaction

Licorice + Fluvastatin

Fluvastatin brand names: Lescol, Lescol XL.

Moderate Interaction
Medically reviewed by · Updated October 2026
The bottom line Moderate

Fluvastatin falls into 2 drug categories that Licorice can interact with; the most serious is rated moderate. Theoretically, licorice might increase or decrease levels of drugs metabolized by CYP2C9.

Read the full interaction report
SeverityModerate
LikelihoodPossible
Interactions2
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Licorice and Fluvastatin

These two interact in 2 distinct ways. Each one is explained separately below.

Why Are There 2 Interactions?

Licorice interacts with whole categories of medication. Fluvastatin falls into 2 of those categories, so it can interact with Licorice in 2 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Moderate).

Moderate

CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES

1 of 2

Why this applies to Fluvastatin

Fluvastatin falls under CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES — the group Licorice interacts with.

Theoretically, licorice might increase or decrease levels of drugs metabolized by CYP2C9.
There is conflicting evidence about the effect of licorice on CYP2C9 enzyme activity. In vitro research shows that extracts from the licorice species G. glabra and G. uralensis moderately inhibit CYP2C9 isoenzymes. However, evidence from an animal model shows that licorice extract from the species G. uralensis can induce hepatic CYP2C9 activity. Until more is known, licorice should be used cautiously in people taking CYP2C9 substrates.
Severity Moderate Likelihood Possible Evidence D

Interaction 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.

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

Here's the thing about fluvastatin: your liver clears it largely through an enzyme called CYP2C9. Licorice may nudge that enzyme, but the science is genuinely mixed. Some lab studies suggest licorice blocks CYP2C9 (which could let fluvastatin build up, raising the chance of muscle aches or, rarely, liver irritation), while an animal study suggests it speeds the enzyme up (which could weaken your cholesterol control). So we honestly can't say for sure which way it would go.

This is all theoretical, based on test tube and animal work, so I wouldn't lose sleep over it. Occasional culinary licorice is unlikely to matter; regular high-dose supplements are the bigger question. Check with your pharmacist or doctor before combining them, especially given licorice can also raise blood pressure.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Kent UM, Aviram M, Rosenblat M, Hollenberg PF. The licorice root derived isoflavan glabridin inhibits the activities of human cytochrome P450S 3A4, 2B6, and 2C9. Drug Metab Dispos 2002;30:709-15.. PubMed
  2. Mu Y, Zhang J, Zhang S, et al. Traditional Chinese medicines Wu Wei Zi (Schisandra chinensis Baill) and Gan Cao (Glycyrrhiza uralensis Fisch) activate pregnane X receptor and increase warfarin clearance in rats. J Pharmacol Exp Ther 2006;316:1369-77. PubMed
  3. Li G, Simmler C, Chen L, et al. Cytochrome P450 inhibition by three licorice species and fourteen licorice constituents. Eur J Pharm Sci. 2017;109:182-190. PubMed
Moderate

CYTOCHROME P450 2C8 (CYP2C8) SUBSTRATES

2 of 2

Fluvastatin also falls under CYTOCHROME P450 2C8 (CYP2C8) SUBSTRATES.

Theoretically, licorice might increase levels of drugs metabolized by CYP2C8.
In vitro, licorice extract from the species G. glabra and G. uralensis inhibits CYP2C8 isoenzymes. Theoretically, these species of licorice might increase levels of drugs metabolized by CYP2C8; however, this interaction has not yet been reported in humans.
Severity Moderate Likelihood Possible Evidence D

Interaction 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.

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

Here's the gist: in lab studies, certain licorice extracts have been shown to slow down an enzyme called CYP2C8, which is one of the routes your body uses to clear fluvastatin. If that enzyme is dialed back, fluvastatin could theoretically build up a bit more than usual. Since fluvastatin is already active when you take it (it's not a prodrug that needs activating), higher levels would mean stronger effects, including a slightly bigger chance of muscle aches, weakness, or, rarely, liver or muscle problems.

The important caveat: this is based only on test-tube data and has never actually been reported in people, so it's mostly theoretical. Still, large or long-term licorice use can also raise blood pressure and lower potassium on its own. I'd just run it past your pharmacist or doctor before combining the two.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Li G, Simmler C, Chen L, et al. Cytochrome P450 inhibition by three licorice species and fourteen licorice constituents. Eur J Pharm Sci. 2017;109:182-190. 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

Licorice Also Interacts With Other Medications

Licorice has 977 moderate, 63 minor known drug interactions in our database — the Fluvastatin one above is among them. If you take anything else, check it against the full list below.

Moderate 977 Minor 63 No known interaction 1,790 (incl. Fluvastatin)
Taking anything else?

Check Another of Your Medications Against Licorice

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

From our Q&A

Questions About Licorice or Fluvastatin

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Licorice or Fluvastatin, 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 Fluvastatin

This page covers Licorice only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Fluvastatin page lists 128 supplements it has a documented interaction with, worst first, each one explained.

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

By severity: 7 major · 97 moderate · 24 minor.

Open the Fluvastatin interaction page

One more smart check

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

We hold 4,721 real supplement products containing Licorice, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Licorice. Your product may carry other ingredients that interact with Fluvastatin too, on top of Licorice — 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 Licorice and Fluvastatin 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 Licorice
Top 5%

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

29 days ago today
Medication Fluvastatin
Steady interest

#2,245 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 Licorice

What is Licorice?

Licorice
  • Sore throat and cough
  • Heartburn and stomach upset
  • Mouth ulcers and digestive complaints
  • Inflammation
  • Traditional tonic/adrenal support

Licorice root is a traditional remedy used for sore throats, coughs, and digestive complaints, but solid human evidence is limited for most uses. Regular licorice contains glycyrrhizin, which can raise blood pressure and lower potassium when taken in large amounts or for a long time, so deglycyrrhizinated (DGL) products are often preferred. Talk to your pharmacist or doctor before using it, especially if you have high blood pressure, heart, or kidney problems.

Read the full Licorice monograph & all interactions
Medication

About Fluvastatin

What Is Fluvastatin Used For?

Brand names: Lescol, Lescol XL

Fluvastatin is used along with a healthy diet to lower cholesterol. It is also used in people who already have coronary heart disease.

Uses differ by product. Fluvastatin capsules are approved for primary hypercholesterolemia (high cholesterol) and mixed dyslipidemia in adults. They are also approved for boys and post-menarchal girls ages 10 to 16 with heterozygous familial hypercholesterolemia (an inherited form of high cholesterol). Fluvastatin extended-release tablets, including Lescol XL, are approved for adults with primary hyperlipidemia. They are also approved for adults and children 10 and older with heterozygous familial hypercholesterolemia who need an 80 mg daily dose. Both forms are used in adults with coronary heart disease to lower the chance of needing a procedure to restore blood flow to the heart and to slow plaque buildup in the heart arteries.

See full Fluvastatin drug information
Keep checking

Other Drugs & Licorice

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

0Major
977Moderate
63Minor
1,789No known interaction
977 Moderate 63 Minor 1,789 No interaction
Moderate

977 interactions

Showing 60 of 977 moderate interactions — see all 977 on the Licorice page.

Minor

63 interactions

Showing 60 of 63 minor interactions — see all 63 on the Licorice page.

No interaction 1,789 drugs checked — show the list

We also checked Licorice against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 1,789 medications checked with no known interaction — see the full Licorice list.

See the full Licorice interactions page
See every supplement checked against Fluvastatin, ranked by severity
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

Keep exploring
Licorice monograph › Uses, safety, and every drug interaction in one place Fluvastatin supplement interactions › Every supplement checked against Fluvastatin, ranked by severity Fluvastatin drug information › The full plain-English guide to this medication Supplement interaction checker › Check any supplement or product against your medications Browse medications A–Z › Every drug we've checked against herbs & supplements Ask a pharmacist › Free, personal answer from our licensed team
Pharmacist Counseling Corner

Taking Licorice and Fluvastatin Together: Common Questions

Can you take Licorice with Fluvastatin?
There is a moderate interaction, so it may be acceptable with monitoring or timing changes — but check with your pharmacist first. Read the full details on this page and confirm with your pharmacist before combining them.
Why are there 2 interactions listed for Licorice and Fluvastatin?
Fluvastatin belongs to more than one drug category, and Licorice interacts with each of those categories a little differently. We list every one so nothing is missed — your overall risk is driven by the most serious of them.
How serious is the Licorice and Fluvastatin interaction?
We rate it Moderate. This combination may require monitoring, a dose adjustment, or separating the times you take each one. Consult your pharmacist before using them together.

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

Still Have a Question About Fluvastatin and Licorice?

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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.