Warfarin with Bee Pollen Interaction Details
Brand Names Associated with Warfarin
- Coumadin®
- Jantoven®
- Warfarin
Medical Content Editor Dr. Brian Staiger, PharmD
Last updated
Nov 07, 2023
Interaction Effect
Increased International Normalized Ratio (INR)
Interaction Summary
Concomitant use of bee pollen and warfarin may result in an elevated INR. A case report demonstrated an association between bee pollen use and elevated INR in a patient who was stabilized on warfarin therapy. The mechanism of this interaction is theorized to be inhibition of the warfarin metabolism via CYP2C9 by the flavonoid components of bee pollen. In this case, the patient was managed successfully with increased INR monitoring and a reduced warfarin dosage. Monitor INR with the addition and withdrawal of bee pollen, and periodically during concurrent therapy. Warfarin dosage adjustments may be required to maintain the desired level of anticoagulation.
Severity
Moderate
Onset
Unspecified
Evidence
Probable
How To Manage Interaction
Concurrent administration of warfarin and bee pollen may elevate the International Normalized Ratio (INR). In patients receiving bee pollen and warfarin, the INR should be monitored with the addition and withdrawal of bee pollen, and periodically during concurrent therapy. Warfarin dosage adjustments may be required to maintain the desired level of anticoagulation.
Mechanism Of Interaction
Inhibition of CYP2C9-mediated warfarin metabolism by flavonoids in bee pollen
Literature Reports
A) A 71-year-old man experienced an elevated INR following concomitant use of warfarin and bee pollen. The patient had been taking warfarin for 3 years with a goal INR of 2 to 3. His concomitant medications were hydrochlorothiazide 25 mg daily, lisinopril 40 mg daily, levothyroxine 200 mcg daily, simvastatin 80 mg nightly, glyburide 2.5 mg twice daily, metformin 1000 mg twice daily, aspirin 81 mg daily, vardenafil 10 mg before sexual activity, a daily multivitamin, and the herbal supplements Cataplex E2(R) 2 tablets twice daily, Cataplex B(R) 2 tablets twice daily, and Cyruta(R) 2 tablets twice daily. He had been stable on warfarin 47.5 mg weekly with therapeutic INRs (range, 1.9 to 3.3) for 9 months when he began taking bee pollen granules one teaspoon by mouth twice a day. One month later his routine INR was 7.1. The patient denied changes in other medications or supplements, had maintained the same diet low in phytonadione, did not consume any alcohol or tobacco, nor had he experienced any recent acute illness. He denied any signs and symptoms of bleeding or bruising. The only other abnormal laboratory test was a slightly elevated total bilirubin (1.4 mg/dL (24 mcmol/L)). His warfarin dose was withheld for 3 days, and on day 4 his INR was 3.7. He was instructed to hold warfarin for 1 more day, then resume at 42.5 mg weekly (an 11% decrease). Upon follow-up 1 week later, his INR was 2.6. He continued taking bee pollen, and with the new warfarin dosage his INRs remained in therapeutic range for the next 7 months .
Warfarin Overview
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Warfarin is used to prevent blood clots from forming or growing larger in your blood and blood vessels. It is prescribed for people with certain types of irregular heartbeat, people with prosthetic (replacement or mechanical) heart valves, and people who have suffered a heart attack. Warfarin is also used to treat or prevent venous thrombosis (swelling and blood clot in a vein) and pulmonary embolism (a blood clot in the lung). Warfarin is in a class of medications called anticoagulants ('blood thinners'). It works by decreasing the clotting ability of the blood.
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Definitions
Severity Categories
Contraindicated
These drugs, generally, should not be used together simultaneously due to the high risk of severe adverse effects. Combining these medications can lead to dangerous health outcomes and should be strictly avoided unless otherwise instructed by your provider.
Major
This interaction could result in very serious and potentially life-threatening consequences. If you are taking this drug combination, it is very important to be under close medical supervision to minimize severe side effects and ensure your safety. It may be necessary to change a medication or dosage to prevent harm.
Moderate
This interaction has the potential to worsen your medical condition or alter the effectiveness of your treatment. It's important that you are monitored closely and you potentially may need to make adjustments in your treatment plan or drug dosage to maintain optimal health.
Minor
While this interaction is unlikely to cause significant problems, it could intensify side effects or reduce the effectiveness of one or both medications. Monitoring for changes in symptoms and your condition is recommended, and adjustments may be made if needed to manage any increased or more pronounced side effects.
Onset
Rapid: Onset of drug interaction typically occurs within 24 hours of co-administration.
Delayed: Onset of drug interaction typically occurs more than 24 hours after co-administration.
Evidence
Level of documentation of the interaction.
Established: The interaction is documented and substantiated in peer-reviewed medical literature.
Theoretical: This interaction is not fully supported by current medical evidence or well-documented sources, but it is based on known drug mechanisms, drug effects, and other relevant information.
How To Manage The Interaction
Provides a detailed discussion on how patients and clinicians can approach the identified drug interaction as well as offers guidance on what to expect and strategies to potentially mitigate the effects of the interaction. This may include recommendations on adjusting medication dosages, altering the timing of drug administration, or closely monitoring for specific symptoms.
It's important to note that all medical situations are unique, and management approaches should be tailored to individual circumstances. Patients should always consult their healthcare provider for personalized advice and guidance on managing drug interactions effectively.
Mechanism Of Interaction
The theorized or clinically determined reason (i.e., mechanism) why the drug-drug interaction occurs.
Disclaimer: The information provided on this page is for informational purposes only and should not be considered medical advice. Always consult with a qualified healthcare professional regarding your specific circumstances and medical conditions.
Where Does Our Information Come From?
Information for our drug interactions is compiled from several drug compendia, including:
The prescribing information for each drug, as published on DailyMED, is also used.
Individual drug-drug interaction detail pages contain references specific to that interaction. You can click on the reference number within brackets '[]' to see what reference was utilized.
The information posted is fact-checked by HelloPharmacist clinicians and reviewed quarterly.