Grapefruit Juice May Increase Blood Levels of Certain Cancer Drugs
In an exciting new study, researchers at the University of Chicago have discovered that drinking grapefruit juice may increase the efficacy of some cancer-fighting drugs by three times.
Grapefruit juice slows down the metabolism of the drug in the body, which can help patients avoid side effects that come with high dosages and reduce the amount of money spent on medication.
One hundred thirty-eight patients with incurable cancer were recruited to participate in this study. One third of the group received only the drug sirolimus, one third received sirolimus and ketoconazole, and one third received sirolimus and grapefruit juice. Ketoconazole is a drug that has been shown in previous studies to slow down the metabolism of other drugs.
By gradually increasing the amount of the drug consumed by the sirolimus-only group, the researchers determined that 90 mg per week was the optimal dosage when taken by itself. At the same time, they noted that anything over 45 mg per week caused sides effects that included nausea and diarrhea.
In contrast, the sirolimus and ketoconazole group only had to consume 16 mg per day of sirolimus to acheive the same blood levels as the sirolimus-only group. The grapefruit juice and sirolimus group needed 25 to 35 mg per week of the drug to maintain the same blood levels.
The researchers noted that, despite the fact that more sirolimus was needed with grapefruit juice than with ketoconazole, grapefruit juice is non-toxic and therefore there is no fear of overdose.
The study was published online ahead of print on August 7, 2012, in the journal Clinical Cancer Research.
Grapefruits are rich in antioxidants and vitamin C. They have been shown to help ease arthritis symptoms, lower cholesterol and promote better digestion.