Drug & supplement interaction

Bupleurum + 6-Mercaptopurine

6-Mercaptopurine brand name: Purinethol.

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

Bupleurum has a moderate interaction with 6-Mercaptopurine. Theoretically, bupleurum might decrease the effects of immunosuppressants.

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

Bupleurum and 6-Mercaptopurine

Here is the interaction we found between these two, with the evidence behind it.

Moderate

IMMUNOSUPPRESSANTS

Why this applies to 6-Mercaptopurine

6-Mercaptopurine falls under IMMUNOSUPPRESSANTS — the group Bupleurum interacts with.

Theoretically, bupleurum might decrease the effects of immunosuppressants.
In vitro and animal research suggests that bupleurum might stimulate immune function.
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 idea behind this pairing. 6-Mercaptopurine (Purinethol) works partly by calming and suppressing the immune system, which is helpful when treating leukemia. Bupleurum, on the other hand, has shown in lab and animal studies that it may stimulate immune activity. So in theory, taking bupleurum could push against what your medication is trying to do and make it work a little less reliably.

I want to be straight with you: this is a theoretical concern based only on test-tube and animal research, not human studies, so we don't truly know how much it matters in real life. Still, with a serious medication like this one, it's not worth the gamble. Please check with your oncologist or pharmacist before adding bupleurum or any herbal formula.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Matsumoto T, Yamada H. Regulation of immune complexes binding of macrophages by pectic polysaccharide from Bupleurum falcatum L.: pharmacological evidence for the requirement of intracellular calcium/calmodulin on Fc receptor up-regulation by bupleuran 2
  2. Kato M, Pu MY, Isobe K, et al. Characterization of the immunoregulatory action of saikosaponin-d. Cell Immunol 1994;159:15-25. PubMed
  3. Ushio Y, Oda Y, Abe H. Effect of saikosaponin on the immune responses in mice. Int J Immunopharmacol 1991;13:501-8. 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

Bupleurum Also Interacts With Other Medications

Bupleurum has 326 moderate known drug interactions in our database — the 6-Mercaptopurine one above is one of them. If you take anything else, check it against the full list below.

Moderate 326 No known interaction 2,504 (incl. 6-Mercaptopurine)
Taking anything else?

Check Another of Your Medications Against Bupleurum

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

From our Q&A

Questions About Bupleurum or 6-Mercaptopurine

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Bupleurum or 6-Mercaptopurine, 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 6-Mercaptopurine

This page covers Bupleurum only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the 6-Mercaptopurine page lists 106 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 Active Hexose Correlated Compound (ahcc) (moderate).

By severity: 4 major · 92 moderate · 10 minor.

From our pharmacist’s overview on the 6-Mercaptopurine page

“6-Mercaptopurine (Purinethol) works by dialing down your immune system, whether for leukemia or inflammatory bowel disease, and that makes this a list to check with real care. The four major-rated entries come first.”

Reviewed by 2 · Jul 18, 2026

Open the 6-Mercaptopurine interaction page

One more smart check

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

We hold 89 real supplement products containing Bupleurum, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Bupleurum. Your product may carry other ingredients that interact with 6-Mercaptopurine too, on top of Bupleurum — 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 Bupleurum and 6-Mercaptopurine 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 Bupleurum
Top half

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

29 days ago today
Medication 6-Mercaptopurine
Steady interest

#1,598 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 Bupleurum

What is Bupleurum?

Bupleurum
  • Liver and digestive support
  • Cold, flu, and fever
  • Inflammation
  • Stress and mood
  • Immune support

Bupleurum (Chai Hu) is a root used in traditional Chinese medicine, usually as part of multi-herb formulas, for liver, digestive, and fever-related complaints. High-quality human evidence for its benefits is limited, and it has been linked to lung and liver problems in some reports, so use it cautiously and only under professional guidance.

Read the full Bupleurum monograph & all interactions
Medication

About Mercaptopurine

What Is Mercaptopurine Used For?

Brand name: Purinethol

Mercaptopurine — available as a tablet and as an oral suspension — is used to treat acute lymphoblastic leukemia (ALL), a type of blood cancer. It is given as part of a combination chemotherapy maintenance regimen, meaning it works alongside other cancer medicines to keep leukemia in remission.

Both the tablet form and the oral suspension form carry this indication for adult and pediatric patients. The oral suspension is particularly useful for patients who cannot swallow tablets.

See full Mercaptopurine drug information
Keep checking

Other Drugs & Bupleurum

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

0Major
326Moderate
0Minor
2,503No known interaction
326 Moderate 2,503 No interaction
Moderate

326 interactions

Showing 60 of 326 moderate interactions — see all 326 on the Bupleurum page.

No interaction 2,503 drugs checked — show the list

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

Showing the 60 most looked-up of 2,503 medications checked with no known interaction — see the full Bupleurum list.

See the full Bupleurum interactions page
See every supplement checked against 6-Mercaptopurine, 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
Bupleurum monograph › Uses, safety, and every drug interaction in one place 6-Mercaptopurine supplement interactions › Every supplement checked against 6-Mercaptopurine, ranked by severity Mercaptopurine 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 Bupleurum and 6-Mercaptopurine Together: Common Questions

Can you take Bupleurum with 6-Mercaptopurine?
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.
How serious is the Bupleurum and 6-Mercaptopurine 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 6-Mercaptopurine and Bupleurum?

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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.