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Hidden sources of grapefruit in beverages: potential interactions with immunosuppressant medications
Ashley A Auten1, Lauren N Beauchamp1, Joshua Taylor1
1PharmD Candidate.
Purpose:
The interaction between grapefruit-containing beverages and immunosuppressants is not well defined in the literature. This study was conducted to investigate possible sources of grapefruit juice or grapefruit extract in common US-manufactured beverages. The goal was to identify those products that might serve as hidden sources of dietary grapefruit intake, increasing a transplant patient's risk for drug interactions.
Methods:
A careful review of the ingredients of the 3 largest US beverage manufacturer's product lines was conducted through manufacturer correspondence, product labeling examination, and online nutrition database research. Focus was placed on citrus-flavored soft drinks, teas, and juice products and their impact on a patient's immunosuppressant regimens.
Results:
Twenty-three beverages were identified that contained grapefruit. Five did not contain the word "grapefruit" in the product name. In addition to the confirmed grapefruit-containing products, 17 products were identified as possibly containing grapefruit juice or grapefruit extract.
Conclusion:
A greater emphasis should be placed upon properly educating patients regarding hidden sources of grapefruit in popular US beverages and the potential for food-drug interactions.
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