Drug & supplement interaction

Bulbine Natalensis + Gilteritinib Fumarate

Gilteritinib Fumarate brand name: Xospata.

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

Gilteritinib Fumarate falls into 2 drug categories that Bulbine Natalensis can interact with; the most serious is rated moderate. Theoretically, Bulbine natalensis stem might reduce the levels and clinical effects of CYP3A4 substrates.

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

Bulbine Natalensis and Gilteritinib Fumarate

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

Why Are There 2 Interactions?

Bulbine Natalensis interacts with whole categories of medication. Gilteritinib Fumarate falls into 2 of those categories, so it can interact with Bulbine Natalensis 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 Gilteritinib Fumarate

Gilteritinib Fumarate falls under CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES — the group Bulbine Natalensis interacts with.

Theoretically, Bulbine natalensis stem might reduce the levels and clinical effects of CYP3A4 substrates.
In vitro research shows that Bulbine natalensis stem extract induces CYP3A4 mRNA expression and enzyme activity. Theoretically, this may increase the metabolism of CYP3A4 substrates, but this has not been studied 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 concern with pairing this supplement and your leukemia medicine. Gilteritinib (Xospata) is cleared from your body mainly by a liver enzyme called CYP3A4. In lab studies, Bulbine natalensis appears to speed up that enzyme. If that happens in people, your body could break down gilteritinib faster than intended, leaving less of it in your blood. For a cancer drug, that's a real worry, because weaker levels could mean it doesn't fight the AML as well as it should.

I want to be honest about the evidence: this is only a theory based on test-tube research, and it hasn't been studied in humans. Still, given how important gilteritinib is, I would not gamble on it. Please check with your oncologist or pharmacist before using this supplement.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Husain I, Dale OR, Manda V, et al. Bulbine natalensis (currently Bulbine latifolia) and select bulbine knipholones modulate the activity of AhR, CYP1A2, CYP2B6, and P-gp. Planta Med 2022;88(12):975-984. PubMed
Moderate

P-GLYCOPROTEIN SUBSTRATES

2 of 2

Gilteritinib Fumarate also falls under P-GLYCOPROTEIN SUBSTRATES.

Theoretically, Bulbine natalensis stem might increase the levels and clinical effects of p-glycoprotein substrates.
In vitro research shows that Bulbine natalensis stem extract induces p-glycoprotein mRNA expression; however, effects on transporter expression were not evaluated.
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 for anyone taking Xospata (gilteritinib) for AML. This leukemia drug is carried around by a transporter pump in your body called P-glycoprotein. Gilteritinib is the active medicine itself, not a prodrug, so it doesn't need to be turned on by anything first.

The lab note on file actually points one way more than the database summary suggests: Bulbine natalensis appeared to turn up P-glycoprotein in a test-tube study, which could pump gilteritinib out faster and theoretically lower its blood levels and how well it fights the cancer. But honestly, this is only a cell study, with no human data, and Bulbine itself carries liver and kidney concerns. Given how important gilteritinib is, please don't add this supplement without first clearing it with your oncologist or pharmacist.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Husain I, Manda V, Alhusban M, et al. Modulation of CYP3A4 and CYP2C9 activity by Bulbine natalensis and its constituents: An assessment of HDI risk of B. natalensis containing supplements. Phytomedicine 2021;81:153416. 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

Bulbine Natalensis Also Interacts With Other Medications

Bulbine Natalensis has 919 moderate known drug interactions in our database — the Gilteritinib Fumarate one above is among them. If you take anything else, check it against the full list below.

Moderate 919 No known interaction 1,911 (incl. Gilteritinib Fumarate)
Taking anything else?

Check Another of Your Medications Against Bulbine Natalensis

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

Everything else you take

See Every Supplement That Interacts With Gilteritinib Fumarate

This page covers Bulbine Natalensis only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Gilteritinib Fumarate page lists 144 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Grapefruit (major), St. John's Wort (major), Acacia Rigidula (moderate) and Adrafinil (moderate).

By severity: 3 major · 103 moderate · 38 minor.

From our pharmacist’s overview on the Gilteritinib Fumarate page

“Anyone taking gilteritinib fumarate (Xospata) is treating FLT3-mutated acute myeloid leukemia, and that alone makes this list one to approach with real vigilance. Of the 144 supplements and herbs on file, three carry a major rating, and they pull in different directions: grapefruit can raise gilteritinib levels, St.”

Reviewed by 2 · Jul 18, 2026

Open the Gilteritinib Fumarate interaction page

One more smart check

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

We hold 51 real supplement products containing Bulbine Natalensis, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Bulbine Natalensis. Your product may carry other ingredients that interact with Gilteritinib Fumarate too, on top of Bulbine Natalensis — 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 Bulbine Natalensis and Gilteritinib Fumarate 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 Bulbine Natalensis
Top half

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

29 days ago today
Medication Gilteritinib Fumarate
Top 10%

#281 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 Bulbine Natalensis

What is Bulbine Natalensis?

  • Boosting testosterone
  • Improving libido
  • Muscle building and athletic performance
  • General male vitality

Bulbine natalensis is a South African plant marketed mainly as a testosterone-boosting and libido supplement, but the human evidence is essentially absent and most claims come from animal studies. Animal research has also raised concerns about possible liver and kidney harm at higher doses, so caution is warranted. Talk to your pharmacist or doctor before trying it.

Read the full Bulbine Natalensis monograph & all interactions
Medication

About Gilteritinib

What Is Gilteritinib Used For?

Brand name: Xospata

Gilteritinib, sold as Xospata tablets, treats adults with acute myeloid leukemia (AML) that has come back (relapsed) or has not responded to earlier treatment (refractory).

It is only used when a test approved by the FDA shows the leukemia has a FLT3 mutation (a change in the FLT3 gene) in the blood or bone marrow.

See full Gilteritinib drug information
Keep checking

Other Drugs & Bulbine Natalensis

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

0Major
919Moderate
0Minor
1,910No known interaction
919 Moderate 1,910 No interaction
Moderate

919 interactions

Showing 60 of 919 moderate interactions — see all 919 on the Bulbine Natalensis page.

No interaction 1,910 drugs checked — show the list

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

Showing the 60 most looked-up of 1,910 medications checked with no known interaction — see the full Bulbine Natalensis list.

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

Can you take Bulbine Natalensis with Gilteritinib Fumarate?
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 Bulbine Natalensis and Gilteritinib Fumarate?
Gilteritinib Fumarate belongs to more than one drug category, and Bulbine Natalensis 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 Bulbine Natalensis and Gilteritinib Fumarate 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 Gilteritinib Fumarate and Bulbine Natalensis?

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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.