THE EFFECTS OF CAFFEINE AND THEOBROMINE UPON THE FORMATION AND EXCRETION OF URIC ACID

Abstract

Adult [male] subjects (4) were used in the 1st set of experiments, carried out for a period of 10 weeks. With adequate control periods, caffeine and theobromine were given orally in daily doses of 0.25-1.0 gm. of caffeine and 0.5-2.0 gm. of the soluble salts (acetate and salicylate). During this entire period the men were kept on a low purine, low protein diet. In the 2nd set of experiments (3 subjects) the determination of uric acid in the blood and urine was made at 2 and 3 hr. intervals. The results indicate that the uric acid content of the circulating blood is increased after the ingestion of either caffeine or theobromine. Following the ingestion of caffeine, there is evidence of an increased production of uric acid. The formation of uric acid seems to be unchanged by the ingestion of theobromine but the rate of excretion is diminished. The authors do not feel that the increases in uric acid are due to the direct oxidation of these methylated xanthines. Prolonged administration of either caffeine or theobromine depresses the excretory functions of the kidney.