Drug & supplement interaction

Licorice + Bupropion, Naltrexone

Bupropion, Naltrexone brand name: Contrave.

Moderate Interaction
The bottom line Moderate

Licorice has a moderate interaction with Bupropion, Naltrexone. Theoretically, licorice might increase levels of drugs metabolized by CYP2B6.

Read the full interaction report
SeverityModerate
LikelihoodPossible
EvidenceD
What do Severity, Likelihood & Evidence mean?
Know someone taking this? Share
Interaction report

Licorice and Bupropion, Naltrexone

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

Moderate

CYTOCHROME P450 2B6 (CYP2B6) SUBSTRATES

Why this applies to Bupropion, Naltrexone

Bupropion, Naltrexone falls under CYTOCHROME P450 2B6 (CYP2B6) SUBSTRATES — the group Licorice interacts with.

Theoretically, licorice might increase levels of drugs metabolized by CYP2B6.
In vitro research shows that licorice extract and glabridin, a licorice constituent, inhibit CYP2B6 isoenzymes. Licorice extract from the species G. uralensis seems to inhibit CYP2B6 isoenzymes to a greater degree than G. glabra extract in vitro. Theoretically, these species of licorice might increase levels of drugs metabolized by CYP2B6; however, these interactions have 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 Contrave (bupropion plus naltrexone). The bupropion half is processed by a liver enzyme called CYP2B6. In test-tube studies, licorice appears to slow that enzyme down. If that held true in people, it could let bupropion build up a bit, and since bupropion is not a prodrug, more of it in your system can mean stronger effects and more side effects, things like jitteriness, trouble sleeping, a faster heartbeat, headache, or higher blood pressure.

I want to be honest with you though: this is only laboratory data, and it has never actually been reported in real patients, so the concern is theoretical. Separately, regular licorice in large or long-term amounts can raise blood pressure on its own, which matters with this medication. A quick chat with your pharmacist or doctor is the safest move before combining them.

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. 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 976 moderate, 63 minor known drug interactions in our database — the Bupropion, Naltrexone 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 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 Bupropion, Naltrexone

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 Bupropion, Naltrexone, 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 Bupropion, Naltrexone

This page covers Licorice only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Bupropion, Naltrexone page lists 47 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Adrafinil (moderate), African Wild Potato (moderate), Artichoke (moderate) and Astaxanthin (moderate).

By severity: 1 major · 34 moderate · 12 minor.

From our pharmacist’s overview on the Bupropion, Naltrexone page

“Anyone taking Contrave (bupropion with naltrexone) for weight management should treat this list with genuine care, starting with the single major-rated entry, activated charcoal, which can soak up the medication in the gut and sharply blunt its effect. Beyond that, two themes dominate.”

Reviewed by 2 · Jul 18, 2026

Open the Bupropion, Naltrexone 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 Bupropion, Naltrexone 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 Bupropion, Naltrexone 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 Bupropion, Naltrexone
Top half

#1,361 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 Naltrexone and Bupropion

What Is Naltrexone and Bupropion Used For?

Brand name: Contrave

Contrave (naltrexone/bupropion extended-release tablets) is approved to help adults with obesity, or adults who are overweight and have at least one weight-related health condition, lose excess weight and keep it off long term. It is always used together with a reduced-calorie diet and increased physical activity — not as a stand-alone treatment.

Contrave is not approved to treat depression, anxiety, or any other psychiatric condition, and it is not approved for use in anyone under 18 years of age.

See full Naltrexone and Bupropion 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
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
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
Pharmacist Counseling Corner

Taking Licorice and Bupropion, Naltrexone Together: Common Questions

Can you take Licorice with Bupropion, Naltrexone?
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.
How serious is the Licorice and Bupropion, Naltrexone 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 Bupropion, Naltrexone and Licorice?

Our pharmacists answer your medication & supplement questions — free.

Ask a pharmacist

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.