Drug & supplement interaction

Methoxylated Flavones + Pralsetinib

Pralsetinib brand name: Gavreto.

Moderate Interaction
The bottom line Moderate

Pralsetinib falls into 2 drug categories that Methoxylated Flavones can interact with; the most serious is rated moderate. In vitro evidence shows that some methoxylated flavones including tangeretin, nobiletin, and heptamethoxyflavone, inhibit P-glycoprotein.

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

Methoxylated Flavones and Pralsetinib

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

Why Are There 2 Interactions?

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

Moderate

P-GLYCOPROTEIN SUBSTRATES

1 of 2

Why this applies to Pralsetinib

Pralsetinib falls under P-GLYCOPROTEIN SUBSTRATES — the group Methoxylated Flavones interacts with.

In vitro evidence shows that some methoxylated flavones including tangeretin, nobiletin, and heptamethoxyflavone, inhibit P-glycoprotein. Theoretically, these methoxylated flavones might increase absorption and blood levels of drugs that are transported by P-glycoprotein.
Some of these drugs include some chemotherapeutic agents (daunorubicin, docetaxel, etoposide, paclitaxel, vinblastine, vincristine, vindesine), antifungals (ketoconazole, itraconazole), protease inhibitors (amprenavir, indinavir, nelfinavir, saquinavir), H2 antagonists (cimetidine, ranitidine), some calcium channel blockers (diltiazem, verapamil), corticosteroids, erythromycin, cisapride (Propulsid), fexofenadine (Allegra), cyclosporine, loperamide (Imodium), quinidine, 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 gist for Gavreto (pralsetinib): your body uses a kind of cellular bouncer called P-glycoprotein to help push this medicine back out and limit how much gets absorbed. Methoxylated flavones from citrus peel, like nobiletin and tangeretin, may slow that bouncer down. In theory, that could let a bit more pralsetinib into your bloodstream, which might nudge up its effects and side effects, things like fatigue, high blood pressure, swelling, constipation, mouth sores, or changes in blood counts.

I want to be honest about the strength of this, though. It's based only on lab studies, not real patients, so it may not amount to much. A slice of orange is very different from a concentrated supplement. Since pralsetinib is a serious cancer drug, please check with your oncology team or pharmacist before adding these flavones.

References
  1. Takanaga H, Ohnishi A, Yamada S, et al. Polymethoxylated flavones in orange juice are inhibitors of P-glycoprotein but not cytochrome P450 3A4. J Pharmacol Exp Ther 2000;293:230-6. DOI
  2. Feng SL, Yuan ZW, Yao XJ, et al. Tangeretin, a citrus pentamethoxyflavone, antagonizes ABCB1-mediated multidrug resistance by inhibiting its transport function. Pharmacol Res 2016;110:193-204. PubMed
Moderate

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES

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

In vitro evidence suggests that methoxylated flavones might inhibit cytochrome P450 3A4 (CYP3A4). This effect seems to be structure-dependent, and does not occur with all methoxylated flavones. So far this interaction has not been reported in humans. Theoretically, concurrent use of certain methoxylated flavones with drugs metabolized by CYP3A4 might result in increased drug levels and an increased risk for adverse effects.
Some drugs metabolized by CYP1A2 include clozapine (Clozaril), cyclobenzaprine (Flexeril), fluvoxamine (Luvox), haloperidol (Haldol), imipramine (Tofranil), mexiletine (Mexitil), olanzapine (Zyprexa), Pentazocine (Talwin), propranolol (Inderal), tacrine (Cognex), theophylline (Slo-bid, Theo-Dur, others), zileuton (Zyflo), Zolmitriptan (Zomig), 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 short version: your body relies on a liver enzyme called CYP3A4 to break down and clear pralsetinib (Gavreto). Certain methoxylated flavones from citrus peel may slow that enzyme down, at least in lab dishes. If they do the same thing in people, pralsetinib could clear more slowly and build up a bit in your system. That could mean a higher chance of its usual side effects, like high blood pressure, fatigue, swelling, mouth sores, or changes in your blood counts and liver tests.

The good news is that this is only theoretical right now, based on test-tube work and not on real patients, and it doesn't happen with every flavone. Still, since pralsetinib is a serious cancer drug, please run any citrus-peel supplement past your oncologist or pharmacist first.

References
  1. Li Y, Ning J, Wang Y, et al. Drug interaction study of flavonoids toward CYP3A4 and their quantitative structure activity relationship (QSAR) analysis for predicting potential effects. Toxicol Lett. 2018 Sep 15;294:27-36. 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

Methoxylated Flavones Also Interacts With Other Medications

Methoxylated Flavones has 891 moderate known drug interactions in our database — the Pralsetinib one above is among them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Methoxylated Flavones

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

Everything else you take

See Every Supplement That Interacts With Pralsetinib

This page covers Methoxylated Flavones only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Pralsetinib page lists 181 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), American Hellebore (major), Arsenic (major), Beer (major) and Cesium (major).

By severity: 11 major · 134 moderate · 36 minor.

From our pharmacist’s overview on the Pralsetinib page

“With pralsetinib (Gavreto), a targeted therapy for RET-driven lung and thyroid cancers, I would treat this list as required reading rather than background noise. Most of the interactions change how much of the drug the body actually gets: grapefruit can push its levels higher, while St.”

Reviewed by 2 · Jul 18, 2026

Open the Pralsetinib interaction page

How much people look this up

Where Methoxylated Flavones and Pralsetinib 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 Methoxylated Flavones
Steady interest

#1,148 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Pralsetinib
Steady interest

#1,755 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 Methoxylated Flavones

What is Methoxylated Flavones?

  • Antioxidant support
  • Circulation and blood vessel health
  • Anti-inflammatory support
  • Skin and aging support
  • General 'metabolism' or wellness blends

Methoxylated flavones (often called polymethoxyflavones) are a group of plant compounds, found mainly in citrus peel, that include substances like nobiletin and tangeretin. Lab and animal studies suggest possible antioxidant and anti-inflammatory effects, but solid human research is very limited, so their real-world benefits are unproven. Talk with a pharmacist or doctor before using them, especially if you take medicines or are pregnant or breastfeeding.

Read the full Methoxylated Flavones monograph & all interactions
Medication

About Pralsetinib

What Is Pralsetinib Used For?

Brand name: Gavreto

Gavreto (pralsetinib) is used to treat adults with metastatic RET fusion-positive non-small cell lung cancer (NSCLC) — a type of lung cancer that has spread and carries a specific genetic alteration detected by an FDA-approved test.

Gavreto is also approved for adults and children aged 12 and older with advanced or metastatic RET fusion-positive thyroid cancer who need systemic (whole-body) treatment and whose cancer no longer responds to radioactive iodine (when radioactive iodine is an appropriate option). This thyroid cancer use is under accelerated approval, meaning continued approval depends on results from confirmatory clinical trials.

See full Pralsetinib drug information
Keep checking

Other Drugs & Methoxylated Flavones

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

0Major
891Moderate
0Minor
1,938No known interaction
Moderate

891 interactions

Showing 60 of 891 moderate interactions — see all 891 on the Methoxylated Flavones page.

No interaction 1,938 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

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Pharmacist Counseling Corner

Taking Methoxylated Flavones and Pralsetinib Together: Common Questions

Can you take Methoxylated Flavones with Pralsetinib?
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 Methoxylated Flavones and Pralsetinib?
Pralsetinib belongs to more than one drug category, and Methoxylated Flavones 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 Methoxylated Flavones and Pralsetinib 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

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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.