Drug & supplement interaction

Diosmin + Pralsetinib

Pralsetinib brand name: Gavreto.

Moderate Interaction
The bottom line Moderate

Pralsetinib falls into 2 drug categories that Diosmin can interact with; the most serious is rated moderate. Theoretically, diosmin might inhibit the metabolism of CYP3A4 substrates.

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

Diosmin and Pralsetinib

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

Why Are There 2 Interactions?

Diosmin interacts with whole categories of medication. Pralsetinib falls into 2 of those categories, so it can interact with Diosmin 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 3A4 (CYP3A4) SUBSTRATES

1 of 2

Why this applies to Pralsetinib

Pralsetinib falls under CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES — the group Diosmin interacts with.

Theoretically, diosmin might inhibit the metabolism of CYP3A4 substrates.
Laboratory research is conflicting with respect to the effects of diosmin on CYP3A4. Some research suggests that diosmin does not affect CYP3A4 activity. However, other research suggests that diosmin alters the metabolism of carbamazepine, a CYP3A4 substrate. Laboratory and animal research show that oral administration of diosmin for 7 days prior to oral administration of carbamazepine increases plasma concentrations of carbamazepine, decreases the clearance of carbamazepine, and decreases the formation of carbamazepine's active metabolite. Additionally, pharmacokinetic research in healthy male subjects shows that taking diosmin (Venex) 500 mg daily for 10 days prior to oral administration of carbamazepine 200 mg increases blood levels of carbamazepine by approximately 58% and decreases carbamazepine clearance by 42%. It is speculated that diosmin reduces the metabolism of carbamazepine by inhibiting CYP3A4. Diosmetin, a metabolite of diosmin, may also inhibit CYP3A4.
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 gist: your body clears pralsetinib partly through a liver enzyme called CYP3A4. Diosmin may gently slow that same enzyme down. If it does, pralsetinib could clear more slowly and build up in your blood, which can mean stronger side effects. With this drug that might look like more fatigue, high blood pressure, swelling, mouth sores, constipation or diarrhea, or changes in blood counts and liver tests.

Now, the honest part: this is mostly theoretical. The clearest data comes from a different drug (carbamazepine), and lab results on diosmin and CYP3A4 are mixed. Since pralsetinib is a serious cancer medicine, please don't start diosmin on your own. Run it by your oncology pharmacist or doctor first so they can decide if it's safe for you.

References
  1. Bedada SK, Neerati P. Modulation of CYP3A enzyme activity by diosmin and its consequence on carbamazepine pharmacokinetics in rats. Naunyn Schmiedebergs Arch Pharmacol. 2018;391(2):115-21. PubMed
  2. Burkina V, Zlabek V, Halsne R, Ropstad E, Zamaratskaia G. In vitro effects of the citrus flavonoids diosmin, naringenin and naringin on the hepatic drug-metabolizing CYP3A enzyme in human, pig, mouse and fish. Biochem Pharmacol. 2016;110-111:109-16 PubMed
  3. Bedada SK, Boga PK. Influence of diosmin on the metabolism and disposition of carbamazepine in healthy subjects. Xenobiotica. 2017;47(10):879-84. PubMed
Moderate

P-GLYCOPROTEIN SUBSTRATES

2 of 2

Pralsetinib also falls under P-GLYCOPROTEIN SUBSTRATES.

Theoretically, diosmin might increase levels of drugs that are substrates of P-glycoprotein (P-gp).
Preliminary laboratory research suggests that diosmin inhibits P-gp. Additionally, pharmacokinetic research in healthy male subjects shows that taking diosmin (Venex) 500 mg daily for 10 days prior to oral administration of fexofenadine 120 mg increases blood levels of fexofenadine, a P-gp substrate, by approximately 49% and decreases the apparent oral clearance of fexofenadine by 41%. The time taken to reach maximum plasma concentration, the half-life, and the apparent renal clearance of fexofenadine are not affected. For this reason, it is speculated that diosmin inhibits P-gp in the intestine, but not in the kidney or liver.
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: diosmin may gently block a pump in your gut called P-glycoprotein (P-gp), and pralsetinib (Gavreto) is carried by that same pump. When the pump is slowed down, a little more of the drug can get absorbed, so your body could end up with somewhat higher pralsetinib levels.

Pralsetinib works as-is (it is not a prodrug), so higher levels mean a stronger effect and potentially more of its usual side effects, things like high blood pressure, swelling, tiredness, constipation, mouth sores, or changes in blood counts. That said, this is mostly a theoretical concern based on lab data and one study using a different drug, so we don't know how big the effect really is with pralsetinib. Since this is a serious cancer medicine, please run any diosmin supplement past your oncology pharmacist or doctor first.

References
  1. Yoo HH, Lee M, Chung HJ, Lee SK, Kim DH. Effects of diosmin, a flavonoid glycoside in citrus fruits, on P-glycoprotein-mediated drug efflux in human intestinal Caco-2 cells. J Agric Food Chem. 2007 Sep 5;55(18):7620-5. PubMed
  2. Bedada SK, Boga PK, Kotakonda HK. The effect of diosmin on the pharmacokinetics of fexofenadine in healthy human volunteers. Xenobiotica. 2017;47(3):230-35. 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

Diosmin Also Interacts With Other Medications

Diosmin has 883 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 Diosmin

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

Everything else you take

See Every Supplement That Interacts With Pralsetinib

This page covers Diosmin 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

One more smart check

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

We hold 121 real supplement products containing Diosmin, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Diosmin. Your product may carry other ingredients that interact with Pralsetinib too, on top of Diosmin — 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 Diosmin 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 Diosmin
Top half

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

29 days ago today
Medication Pralsetinib
Steady interest

#2,320 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 Diosmin

What is Diosmin?

  • Chronic venous insufficiency
  • Hemorrhoids
  • Leg swelling and heaviness
  • Varicose veins
  • Spider veins

Diosmin is a citrus-derived flavonoid most often used for vein-related problems such as chronic venous insufficiency and hemorrhoids, and it is usually combined with a related flavonoid called hesperidin. Some studies suggest it may help relieve leg swelling and hemorrhoid symptoms, but quality varies. Talk to your pharmacist or doctor before starting it, especially if you are pregnant or breastfeeding.

Read the full Diosmin 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 & Diosmin

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

0Major
883Moderate
0Minor
1,946No known interaction
Moderate

883 interactions

Showing 60 of 883 moderate interactions — see all 883 on the Diosmin page.

No interaction 1,946 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 Diosmin and Pralsetinib Together: Common Questions

Can you take Diosmin 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 Diosmin and Pralsetinib?
Pralsetinib belongs to more than one drug category, and Diosmin 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 Diosmin 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.