Drug & supplement interaction

Licorice + Propranolol

Propranolol brand names: Inderal LA, Inderal, Angilol, Syprol, Inderal Injection, and others.

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

Propranolol falls into 3 drug categories that Licorice can interact with; the most serious is rated moderate. Theoretically, licorice might reduce the effects of antihypertensive drugs.

Read the full interaction report
SeverityModerate
LikelihoodPossible
Interactions3
EvidenceB
What do Severity, Likelihood & Evidence mean?
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Interaction report

Licorice and Propranolol

These two interact in 3 distinct ways. Each one is explained separately below.

Why Are There 3 Interactions?

Licorice interacts with whole categories of medication. Propranolol falls into 3 of those categories, so it can interact with Licorice in 3 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Moderate).

Moderate

ANTIHYPERTENSIVE DRUGS

1 of 3

Why this applies to Propranolol

Propranolol falls under ANTIHYPERTENSIVE DRUGS — the group Licorice interacts with.

Theoretically, licorice might reduce the effects of antihypertensive drugs.
In human research, licorice increases blood pressure in a dose-dependent manner.
Severity Moderate Likelihood Possible Evidence B

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 to know if you take propranolol for blood pressure: licorice can work against it. Regular licorice (the kind with glycyrrhizin) makes your body hold onto sodium and water and lose potassium, which tends to nudge blood pressure up. So while your propranolol is busy slowing your heart rate and relaxing your vessels to bring pressure down, licorice can quietly push in the opposite direction and blunt some of that benefit.

This is more of a concern with concentrated licorice supplements or eating real licorice candy regularly, not the small flavoring amounts in some foods. Deglycyrrhizinated (DGL) products don't carry this risk. Before adding licorice, check with your pharmacist or doctor, especially since low potassium can also affect your heart.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Sigurjonsdottir HA, Ragnarsson J, Franzson L, Sigurdsson G. Is blood pressure commonly raised by moderate consumption of liquorice? J Hum Hypertens 1995;9:345-8.
  2. Sigurjonsdottir HA, Franzson L, Manhem K, et al. Liquorice-induced rise in blood pressure: a linear dose-response relationship. J Hum Hypertens 2001;15:549-52. PubMed
  3. Koster, M. and David, G. K. Reversible severe hypertension due to licorice ingestion. N Engl J Med 1968;278(25):1381-1383. PubMed
Moderate

CYTOCHROME P450 2C19 (CYP2C19) SUBSTRATES

2 of 3

Propranolol also falls under CYTOCHROME P450 2C19 (CYP2C19) SUBSTRATES.

Theoretically, licorice might increase levels of drugs metabolized by CYP2C19.
In vitro, licorice extracts from the species G. glabra and G. uralensis inhibit CYP2C19 isoenzymes in vitro. Theoretically, these species of licorice might increase levels of drugs metabolized by CYP2C19; 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 for your situation. Lab studies suggest licorice may slow down an enzyme called CYP2C19, which is one of the pathways that helps clear propranolol from your body. If that enzyme is blocked, a little more propranolol could hang around, which in theory might make its effects stronger. With propranolol that could mean a slower heart rate, lower blood pressure, dizziness, or feeling unusually tired.

The honest part: this has only been seen in test-tube studies, not in real people, so it's more of a theoretical concern than a proven problem. On top of that, regular (glycyrrhizin-containing) licorice can raise blood pressure on its own, which works against what propranolol is doing. If you use licorice regularly, just run it past your pharmacist or doctor first.

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
Minor

CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES

3 of 3

Propranolol also falls under CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES.

Theoretically, licorice might decrease the levels and clinical effects of CYP1A2 substrates.
In vitro research shows that licorice induces CYP1A2 enzymes.
Severity Minor 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 for propranolol and licorice. Some of your propranolol is cleared by a liver enzyme called CYP1A2, and lab studies suggest licorice may speed that enzyme up a bit. In theory, a faster clearance could lower propranolol levels slightly, which might mean it doesn't control your blood pressure, heart rate, or migraines quite as well as usual.

Honestly, this is a weak, theoretical concern based only on test-tube research, so I wouldn't lose sleep over it. The bigger issue is that regular (glycyrrhizin) licorice can raise blood pressure and drop potassium, which works directly against what propranolol is doing. DGL licorice avoids that. Please check with your pharmacist or doctor before adding it.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Haron MH, Dale O, Martin K, et al. Evaluation of the Herb-Drug Interaction Potential of Commonly Used Botanicals on the US Market with Regard to PXR- and AhR-Mediated Influences on CYP3A4 and CYP1A2. J Diet Suppl 2022. 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 976 moderate, 63 minor known drug interactions in our database — the Propranolol one above is among them. If you take anything else, check it against the full list below.

Moderate 976 Minor 63 No known interaction 1,791 (incl. Propranolol)
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 Propranolol

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 Propranolol, 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 Propranolol

This page covers Licorice only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Propranolol page lists 236 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), American Hellebore (major), American Mistletoe (major), Indian Snakeroot (major) and Tyramine (major).

By severity: 5 major · 194 moderate · 37 minor.

From our pharmacist’s overview on the Propranolol page

“Propranolol (Inderal) slows the heart and lowers blood pressure, which is exactly why its 236-ingredient interaction list deserves genuine care. Five entries rate major, and those are the ones to understand first.”

Reviewed by 2 · Jul 18, 2026

Open the Propranolol 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 Propranolol 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 Propranolol 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%

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

29 days ago today
Medication Propranolol
Top 1%

#11 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 Propranolol (Cardiovascular)

What Is Propranolol (Cardiovascular) Used For?

Brand names: Inderal LA, Inderal, Angilol, Syprol, Inderal Injection, Half-Inderal LA, Bedranol SR, Half Beta Prograne, Beta Prograne, Lopranol LA, Slo-Pro, InnoPran XL

This intravenous (IV) form of propranolol is used in hospital or clinical settings to treat dangerous heart rhythm problems. It is generally reserved for life-threatening arrhythmias (abnormal heart rhythms) or those that occur during anesthesia.

Specific conditions it treats include fast heart rates coming from the upper chambers of the heart (supraventricular tachycardia), certain arrhythmias caused by digitalis toxicity, dangerous ventricular rhythms that haven't responded to other treatments, and fast heart rates caused by excess adrenaline-like substances during surgery.

See full Propranolol (Cardiovascular) 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
976Moderate
63Minor
1,790No known interaction
976 Moderate 63 Minor 1,790 No interaction
Moderate

976 interactions

Showing 60 of 976 moderate interactions — see all 976 on the Licorice page.

Minor

63 interactions

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

No interaction 1,790 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 1,790 medications checked with no known interaction — see the full Licorice list.

See the full Licorice interactions page
See every supplement checked against Propranolol, 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 Propranolol supplement interactions › Every supplement checked against Propranolol, ranked by severity Propranolol (Cardiovascular) 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 Propranolol Together: Common Questions

Can you take Licorice with Propranolol?
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 3 interactions listed for Licorice and Propranolol?
Propranolol 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 Propranolol 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 Propranolol 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.