Drug & supplement interaction

Boswellia Serrata + Zileuton

Zileuton brand names: Zyflo, Zyflo CR.

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

Zileuton falls into 3 drug categories that Boswellia Serrata can interact with; the most serious is rated moderate. Theoretically, Boswellia serrata might increase the levels of CYP1A2 substrates.

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

Boswellia Serrata and Zileuton

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

Why Are There 3 Interactions?

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

Moderate

CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES

1 of 3

Why this applies to Zileuton

Zileuton falls under CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES — the group Boswellia Serrata interacts with.

Theoretically, Boswellia serrata might increase the levels of CYP1A2 substrates.
In vitro research shows that Boswellia serrata gum resin inhibits CYP1A2 enzymes.
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 situation with these two. Your body uses an enzyme called CYP1A2 to help break down and clear Zileuton. In lab (test tube) studies, boswellic acids from Boswellia appear to slow that same enzyme down. If that held true in people, Zileuton could clear a bit more slowly and build up, which might nudge up the chance of its usual side effects like nausea, stomach upset, headache, or changes in liver enzyme levels.

I want to be honest though: this is only a theoretical concern based on lab data, not real patient reports, so I wouldn't lose sleep over it. Since Zileuton already needs liver monitoring, it's worth a quick chat with your pharmacist or doctor before adding Boswellia.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Frank A, Unger M. Analysis of frankincense from various Boswellia species with inhibitory activity on human drug metabolising cytochrome P450 enzymes using liquid chromatography mass spectrometry after automated on-line extraction. J Chromatogr A 2006;111 PubMed
Moderate

CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES

2 of 3

Zileuton also falls under CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES.

Theoretically, Boswellia serrata might increase the levels of CYP2C9 substrates.
In vitro research shows that Boswellia serrata gum resin inhibits CYP2C9 enzymes.
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 Zileuton (Zyflo). Your liver uses an enzyme called CYP2C9 to help clear this medicine. Boswellia, in lab dish studies, seems to slow that same enzyme down. So in theory, taking the two together could let more Zileuton linger in your system than usual, which might nudge up its effects and side effects.

With Zileuton, that could mean a higher chance of things like nausea, stomach upset, headache, or stress on the liver (this drug already requires liver monitoring). I want to be honest though: this is only a theoretical concern based on test-tube data, not real people, so it may not amount to much. Still, it's worth a quick chat with your pharmacist or doctor before combining them.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Frank A, Unger M. Analysis of frankincense from various Boswellia species with inhibitory activity on human drug metabolising cytochrome P450 enzymes using liquid chromatography mass spectrometry after automated on-line extraction. J Chromatogr A 2006;111 PubMed
Moderate

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES

3 of 3

Zileuton also falls under CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES.

Theoretically, Boswellia serrata might increase or decrease the levels and clinical effects of CYP3A4 substrates.
In vitro research shows that Boswellia serrata gum resin inhibits CYP3A4 enzymes. Other in vitro research shows that Boswellia serrata extract inhibits CYP3A4 enzymes at most concentrations, although it may modestly induce enzyme activity at low concentrations.
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 something interesting about pairing boswellia with Zileuton: both work on inflammation, but in different ways. Boswellia blocks the 5-LOX enzyme, while Zileuton (a leukotriene synthesis inhibitor) targets a similar inflammatory pathway. Beyond that overlap, the concern on file is that boswellia may affect CYP3A4, one of the liver enzymes that helps clear Zileuton. In lab studies, boswellia mostly slows CYP3A4 down, which could in theory let Zileuton build up a bit and raise the chance of side effects like nausea, stomach upset, or headache.

I want to be honest though, this is purely theoretical and based on test-tube data, not real patients. It's not a reason to panic. Just mention both to your pharmacist or doctor, since Zileuton already requires liver monitoring.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Frank A, Unger M. Analysis of frankincense from various Boswellia species with inhibitory activity on human drug metabolising cytochrome P450 enzymes using liquid chromatography mass spectrometry after automated on-line extraction. J Chromatogr A 2006;111 PubMed
  2. 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

Boswellia Serrata Also Interacts With Other Medications

Boswellia Serrata has 951 moderate known drug interactions in our database — the Zileuton one above is among them. If you take anything else, check it against the full list below.

Moderate 951 No known interaction 1,879 (incl. Zileuton)
Taking anything else?

Check Another of Your Medications Against Boswellia Serrata

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

Everything else you take

See Every Supplement That Interacts With Zileuton

This page covers Boswellia Serrata only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Zileuton page lists 213 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 St. John's Wort (major).

By severity: 6 major · 163 moderate · 44 minor.

Open the Zileuton interaction page

One more smart check

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

We hold 1,914 real supplement products containing Boswellia Serrata, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Boswellia Serrata. Your product may carry other ingredients that interact with Zileuton too, on top of Boswellia Serrata — 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 Boswellia Serrata and Zileuton 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 Boswellia Serrata
Top 10%

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

29 days ago today
Medication Zileuton
Steady interest

#1,571 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 Boswellia Serrata

What is Boswellia Serrata?

Boswellia Serrata
  • Osteoarthritis joint pain
  • Rheumatoid arthritis
  • Inflammation
  • Asthma
  • Inflammatory bowel conditions

Boswellia serrata is a tree resin used in traditional medicine, mainly for joint pain and inflammation. Some studies suggest it may help with osteoarthritis symptoms, but the overall evidence is limited and more research is needed. It is generally well tolerated, but you should check with your pharmacist or doctor before using it, especially during pregnancy or breastfeeding.

Read the full Boswellia Serrata monograph & all interactions
Medication

About Zileuton

What Is Zileuton Used For?

Brand names: Zyflo, Zyflo CR

Zileuton is used for the ongoing prevention and treatment of asthma in adults and adolescents aged 12 and older. It is a maintenance medicine — meaning it is taken regularly to keep asthma under control, not to stop an asthma attack once it has started.

Zyflo (the tablet form) and zileuton extended-release tablets are both approved for this same purpose. Neither form should be used to treat a sudden asthma attack. However, both can be continued during a flare-up of asthma while you also use your rescue inhaler.

See full Zileuton drug information
Keep checking

Other Drugs & Boswellia Serrata

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

0Major
951Moderate
0Minor
1,878No known interaction
951 Moderate 1,878 No interaction
Moderate

951 interactions

Showing 60 of 951 moderate interactions — see all 951 on the Boswellia Serrata page.

No interaction 1,878 drugs checked — show the list

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

Showing the 60 most looked-up of 1,878 medications checked with no known interaction — see the full Boswellia Serrata list.

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

Can you take Boswellia Serrata with Zileuton?
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 Boswellia Serrata and Zileuton?
Zileuton belongs to more than one drug category, and Boswellia Serrata 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 Boswellia Serrata and Zileuton 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 Zileuton and Boswellia Serrata?

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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.