Drug Interaction Report

Boldo and Epoprostenol: Interaction Details

A pharmacist-reviewed analysis of the Boldo and Epoprostenol interaction: the documented clinical effects, severity rating, onset, mechanism, and management considerations, with cited references throughout.

AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature

Epoprostenol

Flolan Flolan® Veletri Veletri®
+

Boldo

No brand names on record
Dr. Brian Staiger, PharmD, BCPS
Medically reviewed by
Dr. Brian Staiger, PharmD, BCPS
Updated Aug 8, 2026
Editorial policy · Data sources
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Interaction severity
Moderate
Can be significant — usually manageable with monitoring.
How we grade severity & evidence

Severity levels

  • Contraindicated: These should generally not be used together.
  • Major: Potentially serious — often needs a change or close monitoring.
  • Moderate: Can be significant — usually manageable with monitoring.
  • Minor: Usually limited clinical impact.

Evidence grades

  • Established: Well documented — supported by controlled studies or strong clinical data.
  • Probable: Good supporting evidence, though not definitively proven.
  • Suspected: Some evidence suggests this interaction, but it is not well established.
  • Possible: Limited or conflicting evidence; the interaction may occur.
  • Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.

Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.

Of 16 documented Boldo interactions, 16 are rated moderate — including this one.
Onset
delayed
Evidence
theoretical
Severity
Moderate

What happens

Increased risk of bleeding

Interaction Deep Dive

A case report describes an elevated International Normalized Ratio (INR) in a patient stabilized on warfarin following use of boldo and fenugreek2. It is unclear if one or both products led to the increased INR since the two products were used at the same time. Boldo may have antiplatelet activity, while fenugreek contains coumarins which may affect blood coagulation 2. Concomitant use of boldo and antiplatelet agents is not recommended.

Why it happens (mechanism)

Boldo may have antiplatelet activity

Literature reports

1 report — tap to read

a) Boldo or fenugreek may have contributed to an increased International Normalized Ratio (INR) in a 67-year-old female taking warfarin. The patient had a stable INR between 2 and 3 for one year, and during routine testing, the INR was found slightly elevated at 3.4. The patient denied any change in prescription medications, alcohol use, diet, or health. The only change was use of fenugreek (Swiss), 1 capsule before meals, and boldo (Vaugel), 10 drops after meals (unknown formulation) for a few weeks prior to the blood test. One week after discontinuing boldo and fenugreek, the INR was 2.6. She then resumed the boldo and fenugreek, leading to an INR of 3.1 after one week, and 3.4 after two weeks. She refused to discontinue the agents, necessitating a 15% decrease in her weekly warfarin dose to achieve a therapeutic INR. No bleeding complications were experienced by the patient 1.

Common questions

Can I take Boldo and Epoprostenol together?

Increased risk of bleeding Always confirm with your pharmacist or prescriber before making any change.

How serious is the Boldo and Epoprostenol interaction?

It is rated moderate. Can be significant — usually manageable with monitoring.

How quickly could this interaction happen?

The documented onset is "delayed". Effects tend to build up gradually over days to weeks.

How strong is the evidence for this interaction?

The evidence is graded "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.

Questions for your pharmacist

  • Does my dose of Boldo or Epoprostenol need adjusting while I take them together?
  • What symptoms should prompt me to call you or my prescriber right away?
  • Does the timing of my doses matter for this combination?
  • Is there anything you'd monitor while I'm on both?

References (2)

  1. Lambert JP & Cormier J: Potential interaction between warfarin and boldo-fenugreek. Pharmacotherapy 2001; 21(4):509-512. PubMed
  2. Lambert JP & Cormier J: Potential interation between warfarin and boldo-fenugreek. Pharmacotherapy 2001; 21(4):509-512.
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Epoprostenol

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All Epoprostenol interactions (152) Epoprostenol drug information
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Boldo

Keep reading about Boldo

All Boldo interactions (16)
Beyond drug–drug

These medications also interact with supplements

Prescription drugs aren't the whole picture — herbal and dietary supplements can interact with them too. From the evidence-graded Natural Medicines database:

Epoprostenol + Activated Charcoal American Hellebore American Mistletoe Tyramine Adrafinil Agmatine Algal Oil Andrographis + 128 more

major · moderate · minor — check everything you take with our drug–supplement interaction checker.

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This information is for education, not a substitute for professional medical advice. Do not start, stop, or change any medication without talking to your pharmacist or prescriber.