Does rhubarb juice increase International Normalized Ratio (INR) in patients taking warfarin?

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From the Research

Rhubarb juice is unlikely to increase INR in patients taking warfarin, as there is limited evidence to suggest a significant interaction between the two. The most recent and highest quality study on the topic of herbal formulas and warfarin interaction found that the use of herbal formulas may not influence INR value 1. While there are case reports of other substances, such as cranberry juice, interacting with warfarin to increase INR 2, 3, 4, there is no specific evidence to suggest that rhubarb juice has a similar effect. It is still important for patients on warfarin to exercise caution with any dietary changes and inform their healthcare providers about any potential interactions, as individual responses to warfarin can vary greatly due to factors such as age, body weight, and nutritional status 5. Regular INR monitoring is crucial for patients on warfarin, especially when making any changes to their diet or medication regimen. Some key points to consider include:

  • Maintaining consistent intake of rhubarb juice if it is regularly consumed
  • Informing healthcare providers about any rhubarb in the diet
  • Monitoring for unusual bruising, bleeding, or significant INR changes after consuming rhubarb
  • Understanding that individual responses to warfarin can vary greatly due to various patient factors.

References

Research

Warfarin and cranberry juice: an interaction?

The Journal of heart valve disease, 2004

Research

Warfarin-cranberry juice interaction.

The Annals of pharmacotherapy, 2011

Research

Patient factors that influence warfarin dose response.

Journal of pharmacy practice, 2010

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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