Drug & supplement interaction

Boldo + Ropeginterferon alfa-2b-njft

Ropeginterferon alfa-2b-njft brand name: Besremi.

Moderate Interaction
The bottom line Moderate

Boldo has a moderate interaction with Ropeginterferon alfa-2b-njft. Theoretically, taking boldo with hepatotoxic drugs might increase the risk of hepatic injury and disease.

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

Boldo and Ropeginterferon alfa-2b-njft

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

Moderate

HEPATOTOXIC DRUGS

Why this applies to Ropeginterferon alfa-2b-njft

Ropeginterferon alfa-2b-njft falls under HEPATOTOXIC DRUGS — the group Boldo interacts with.

Theoretically, taking boldo with hepatotoxic drugs might increase the risk of hepatic injury and disease.
Boldo leaf contains ascaridole, a known liver toxin. Many cases of hepatotoxicity, including elevated liver transaminase levels and jaundice, have been reported in patients taking boldo.
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 simple version: this isn't a case where Boldo changes how Besremi works. Instead, both can be tough on your liver, so the worry is they add up. Besremi (an interferon) already comes with a known risk of liver strain, and your care team monitors your liver enzymes while you're on it. Boldo leaf contains ascaridole, a compound that has been linked to real cases of liver injury, including raised liver enzymes and jaundice (yellowing of the skin or eyes).

Stacking the two could make liver trouble more likely or harder to spot. To be fair, this concern is mostly theoretical and based on scattered case reports, not strong studies. Still, since your liver is already being watched, please check with your pharmacist or doctor before adding Boldo, and don't change your Besremi on your own.

References
  1. Piscaglia F, Leoni S, Venturi A, et al. Caution in the use of boldo in herbal laxatives: a case of hepatotoxicity. Scand J Gastroenterol 2005;40:236-9. PubMed
  2. Ribeiro RJ, Silvestre C, Duarte C. Hidden risks of alternative medicines: a case of boldo-induced hepatotoxicity. J Diet Suppl 2017;14(2):186-90. PubMed
  3. Oliveira Sá A, Pimentel T, Oliveira N. Boldo-Induced Hepatotoxicity: A Case of Unexplained Jaundice. Eur J Case Rep Intern Med 2020;7(12):002116. 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

Boldo Also Interacts With Other Medications

Boldo has 481 moderate known drug interactions in our database — the Ropeginterferon alfa-2b-njft one above is one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Boldo

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

Everything else you take

See Every Supplement That Interacts With Ropeginterferon alfa-2b-njft

This page covers Boldo only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Ropeginterferon alfa-2b-njft page lists 57 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Beer (major), Siberian Cocklebur (major), Wine (major), Alfalfa (moderate) and Angelica Archangelica (moderate).

By severity: 3 major · 53 moderate · 1 minor.

From our pharmacist’s overview on the Ropeginterferon alfa-2b-njft page

“Ropeginterferon alfa-2b-njft (Besremi), the long-acting interferon injected for polycythemia vera, carries liver toxicity as one of its own known risks, so the 57 supplements and herbs on this page deserve genuine care rather than a quick skim. Thirty-eight of them can also stress the liver, and that overlap is what earns all three maj…”

Reviewed by 2 · Jul 18, 2026

Open the Ropeginterferon alfa-2b-njft interaction page

One more smart check

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

We hold 173 real supplement products containing Boldo, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Boldo. Your product may carry other ingredients that interact with Ropeginterferon alfa-2b-njft too, on top of Boldo — 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 Boldo and Ropeginterferon alfa-2b-njft 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 Boldo
Steady interest

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

29 days ago today
Medication Ropeginterferon alfa-2b-njft
Steady interest

#2,789 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 Boldo

What is Boldo?

Boldo
  • Indigestion and bloating
  • Mild constipation
  • Liver and gallbladder support
  • Appetite stimulation
  • Urinary complaints

Boldo is a South American shrub whose leaves are traditionally used for digestive and gallbladder complaints, but good human evidence is very limited. The leaves and oil contain ascaridole, which can be toxic to the liver, so only ascaridole-free products should be used and only for short periods. Talk to your pharmacist or doctor before trying it, and avoid it during pregnancy and breastfeeding.

Read the full Boldo monograph & all interactions
Medication

About Ropeginterferon alfa-2b

What Is Ropeginterferon alfa-2b Used For?

Brand name: Besremi

BESREMi (ropeginterferon alfa-2b) is used to treat two conditions in adults: polycythemia vera, a bone marrow disorder where the body makes too many red blood cells, and essential thrombocythemia, a condition where the bone marrow makes too many platelets.

Both conditions are given as subcutaneous (under-the-skin) injections of BESREMi, including the BESREMi Pen delivery option.

See full Ropeginterferon alfa-2b drug information
Keep checking

Other Drugs & Boldo

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

0Major
481Moderate
0Minor
2,348No known interaction
Moderate

481 interactions

Showing 60 of 481 moderate interactions — see all 481 on the Boldo page.

No interaction 2,348 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 Boldo and Ropeginterferon alfa-2b-njft Together: Common Questions

Can you take Boldo with Ropeginterferon alfa-2b-njft?
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 Boldo and Ropeginterferon alfa-2b-njft 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.