Objective. To investigate whether fenofibrate increases the clearance of pu
rine bases (hypoxanthine, xanthine, uric acid) and oxypurinol.
Methods. We administered fenofibrate (150 mg) 3 times a day for 3 days, and
then allopurinol (300 mg) 4 h after the last administration of fenofibrate
, to 5 healthy subjects. Ten hours later, a clearance study was done.
Results. Following 3 day administration of fenofibrate, fractional clearanc
e of xanthine, uric acid, and oxypurinol increased by 41% (p < 0.05), 101%
(p < 0.01), and 51% (p < 0.01), respectively, compared to baseline values,
while the respective plasma concentrations decreased by 46% (p < 0.05), 46%
(p < 0.05), and 19% (p < 0.05).
Conclusion. Our results suggest that fenofibrate, fenofibric acid, or fenof
ibrate derivatives can increase fractional clearance of xanthine, uric acid
, and oxypurinol by acting on their common renal pathways. It is suggested
that the hypouricemic effect of combination therapy using allopurinol and f
enofibrate may be less than additive.