The Effect of Allopurinol on Oral Purine Absorption and Excretion in the Pig

Abstract

Allopurinol therapy in hyperuricaemic man has been shown to be advantageous from two points of view. Firstly, it reduces urinary uric acid excretion and increases the excretion of the precursor purines xanthine and, to a lesser extent, hypoxanthine. In addition, total urinary purine excretion (the sum of these three) may be reduced by as much as 50% during allopurinol therapy (1). This latter effect has been attributed to the formation of nucleotides of either hypoxanthine (1) or allopurinol itself (2), which in turn exert a “feed back” inhibitary effect on the first enzyme of de novo purine synthesis.