RESUMO
Introduction: Recently Grapefruit juice is known to enhance the bioavailability of several clinically important drugs such as nifedipine, terfenadine, cyclosporine, ethinylestradiole, midazolam, and triazolam. Cyclosporine is an immunosuppressive agent that used in transplantation for preventation of chronic rejection. Grapefruit increase in C[max] and AUC of drug mediated by suppression of Cyp3A4 in small intestine wall
Methods: This study has been performed by twenty allogenic bone marrow transplant recipients at shariati hospital in Tehran with [Randomized Cross Over Placebo Controlled Study]. Subjects were co administrated oral cyclosporine and grapefruit juice as a controlled and water as a placebo, simultaneously and two hours later. Blood samples were collected at 3.5 and 11.5 hours following drug administration. Blood concentration analyzed by specific monoclonal radioimmunoassay [RIA] technique
Results: SPSS version 11 [2002] was used for data analysis. mean and standerd deviation of cyclosponie C. was [821 +/- 215] ng/ml immediately and 2 hours after using grapefruit, which shows%41 higher levels in compersion to drinking water as placebo [578 +/- 194] ng/ml [p<0/05], but C[min] blood concentration shows only%21 increase with grapefruit versus water as placebo [p>0/05] [319 +/- 173 in grapefrait verus 268 +/- 140 in water]. The averge systolic and diostolic blood pressare was decreased significanty in grapefruit group [p<0/05]
Conclusion: This study demonstrated that administration of grapefruit juice had increased the cyclosporine C[max] [%42] at Iranian bone marrow transplant recipients. Because grapefruit juice may be a safe and effective instrument to enhance absorption of many therapeutic agents, it is an appropriate means in terms of reducing dosing requirements of many Cyp3A4 substrates such as cyclosporine