Drug & supplement interaction

Limonene + Fluconazole

Fluconazole brand names: Diflucan, Diflucan Injection.

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

Fluconazole falls into 2 drug categories that Limonene can interact with; the most serious is rated moderate. There's preliminary evidence that limonene might be a substrate for cytochrome P450 2C19 (CYP2C19).

Read the full interaction report
SeverityModerate
LikelihoodPossible
Interactions2
EvidenceD
What do Severity, Likelihood & Evidence mean?
Know someone taking this? Share
Facebook Post Reddit Email
On this page
Interaction report

Limonene and Fluconazole

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

Why Are There 2 Interactions?

Limonene interacts with whole categories of medication. Fluconazole falls into 2 of those categories, so it can interact with Limonene 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 2C19 (CYP2C19) INHIBITORS

1 of 2

Why this applies to Fluconazole

Fluconazole falls under CYTOCHROME P450 2C19 (CYP2C19) INHIBITORS — the group Limonene interacts with.

There's preliminary evidence that limonene might be a substrate for cytochrome P450 2C19 (CYP2C19). So far, this interaction has not been reported in humans. However, watch for an increase in the limonene levels when it is taken with drugs that inhibit CYP2C19. Some drugs that inhibit CYP2C19 include cimetidine (Tagamet), fluvoxamine (Luvox), omeprazole (Prilosec); ticlopidine (Ticlid), topiramate (Topamax), and others.
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 simple version: fluconazole is one of those medicines that can block an enzyme in your liver called CYP2C19, and early research suggests limonene may be processed by that same enzyme. So in theory, taking concentrated limonene supplements alongside fluconazole could slow down how fast your body clears the limonene, letting a bit more of it build up.

I want to be honest about how soft this is. This is based only on lab and animal data, and it has not been seen in actual people. The concern runs toward the limonene side, not your fluconazole, and your antifungal should still work as intended. A splash of citrus or orange peel in food is no worry. If you're using high-dose limonene capsules, just run it by your pharmacist or doctor first.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Crowell PL. Prevention and therapy of cancer by dietary monoterpenes. J Nutr 1999;129:775S-778S. PubMed
  2. Miyazawa M, Shindo M, Shimada T. Metabolism of (+)- and (-)-limonenes to respective carveols and perillyl alcohols by CYP2C9 and CYP2C19 in human liver microsomes. Drug Metab Dispos 2002;30:602-7. PubMed
Moderate

CYTOCHROME P450 2C9 (CYP2C9) INHIBITORS

2 of 2

Fluconazole also falls under CYTOCHROME P450 2C9 (CYP2C9) INHIBITORS.

There's preliminary evidence that limonene might be a substrate for cytochrome P450 2C9 (CYP2C9). So far, this interaction has not been reported in humans. However, watch for side effects in patients taking limonene and CYP2C9 inhibitors. Some CYP2C9 inhibitors include amiodarone (Cordarone), fluconazole (Diflucan), lovastatin (Mevacor), paroxetine (Paxil), zafirlukast (Accolate), and many others.
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 to understand: in this pairing, fluconazole (Diflucan) is the one doing the blocking, and limonene is along for the ride. Fluconazole slows down a liver enzyme called CYP2C9, and early lab work hints that limonene may be broken down by that same enzyme. If fluconazole blocks it, limonene could clear more slowly and linger in your body a bit longer than usual.

What does that mean in real life? Honestly, not much for most people. This idea comes only from test tube and animal studies, and it has never actually been reported in humans. If anything, you might just notice more of limonene's mild effects, like a touch of heartburn or stomach upset. Fluconazole itself works the same either way. Still, mention any supplements to your pharmacist so we can keep an eye out.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Crowell PL. Prevention and therapy of cancer by dietary monoterpenes. J Nutr 1999;129:775S-778S. PubMed
  2. Miyazawa M, Shindo M, Shimada T. Metabolism of (+)- and (-)-limonenes to respective carveols and perillyl alcohols by CYP2C9 and CYP2C19 in human liver microsomes. Drug Metab Dispos 2002;30:602-7. 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

Limonene Also Interacts With Other Medications

Limonene has 228 moderate known drug interactions in our database — the Fluconazole one above is among them. If you take anything else, check it against the full list below.

Moderate 228 No known interaction 2,602 (incl. Fluconazole)
Taking anything else?

Check Another of Your Medications Against Limonene

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

From our Q&A

Questions About Limonene or Fluconazole

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

This page covers Limonene only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Fluconazole page lists 81 supplements it has a documented interaction with, worst first, each one explained.

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

By severity: 4 major · 54 moderate · 23 minor.

From our pharmacist’s overview on the Fluconazole page

“Fluconazole (Diflucan) treats fungal infections, and I would pair it with supplements carefully. Nearly half of the 81 ingredients with an interaction on file, 38 of them, put extra strain on the liver, which is already busy processing the antifungal.”

Reviewed by 2 · Jul 18, 2026

Open the Fluconazole interaction page

One more smart check

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

We hold 89 real supplement products containing Limonene, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Limonene. Your product may carry other ingredients that interact with Fluconazole too, on top of Limonene — 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 Limonene and Fluconazole 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 Limonene
Steady interest

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

29 days ago today
Medication Fluconazole
Top half

#906 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 Limonene

What is Limonene?

  • Heartburn and acid reflux
  • Digestive upset
  • Stress and mood support
  • Antioxidant support
  • General wellness

Limonene is a natural compound found in the peel of citrus fruits like oranges and lemons, and it is used as a flavoring agent and dietary supplement. People take it for heartburn, digestion, and general wellness, but solid human evidence is limited. It is generally well tolerated in food amounts, but talk with your pharmacist or doctor before using concentrated supplements.

Read the full Limonene monograph & all interactions
Medication

About Fluconazole

What Is Fluconazole Used For?

Brand names: Diflucan, Diflucan Injection

Fluconazole treats infections caused by Candida and Cryptococcus fungi. Diflucan tablets and oral suspension, fluconazole tablets, and fluconazole oral suspension and tablets are approved for vaginal yeast infections (vaginal candidiasis), mouth and throat yeast infections (oropharyngeal candidiasis), and esophageal candidiasis. All formulations, including the intravenous injection, are used for cryptococcal meningitis (a fungal infection of the brain lining). In smaller studies, fluconazole was also effective for Candida urinary tract infections, peritonitis (abdominal lining infection), and serious systemic infections such as candidemia (Candida in the bloodstream) and disseminated candidiasis.

Fluconazole is also used as preventive therapy: Diflucan, fluconazole tablets, fluconazole oral suspension, and fluconazole injection are all indicated to reduce the risk of candidiasis in patients undergoing bone marrow transplantation who receive chemotherapy and/or radiation therapy. Note that the oral suspension formulations are not approved for vaginal candidiasis — that indication applies only to Diflucan tablets/suspension and fluconazole tablets/tablet-suspension products.

See full Fluconazole drug information
Keep checking

Other Drugs & Limonene

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

0Major
228Moderate
0Minor
2,601No known interaction
228 Moderate 2,601 No interaction
Moderate

228 interactions

Showing 60 of 228 moderate interactions — see all 228 on the Limonene page.

No interaction 2,601 drugs checked — show the list

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

Showing the 60 most looked-up of 2,601 medications checked with no known interaction — see the full Limonene list.

See the full Limonene interactions page
See every supplement checked against Fluconazole, 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
Limonene monograph › Uses, safety, and every drug interaction in one place Fluconazole supplement interactions › Every supplement checked against Fluconazole, ranked by severity Fluconazole 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 Limonene and Fluconazole Together: Common Questions

Can you take Limonene with Fluconazole?
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 Limonene and Fluconazole?
Fluconazole belongs to more than one drug category, and Limonene 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 Limonene and Fluconazole 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 Fluconazole and Limonene?

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.