医薬品の吸収と排泄に関する研究 (第12報)

サリチル酸誘導体の排泄ならびに体内変化と尿のpHの関係

抄録

Examinations were made on the relationship between urinary excretion, metabolites, and urine pH after administration of salicylic acid derivatives (salicylic acid, gentisic acid, p-aminosalicylic acid, and salicylamide) in man. In the case of acid urine, excretion of unchanged salicylic acid and PAS was small and markedly increased in the case of alkaline urine. Amount of gentisic acid increased only slightly and that of salicylamide remained entirely unchanged. This is thought to be because the non-dissociated form is more easily re-absorbed than the dissociated form through the urinary duct and is less absorbed, the smaller the distribution coefficients between organic solvents. The difference in the rate of change in the body between acid and alkaline urine was smaller, the greater the excretion velocity. It was found that excretion of p-aminosalicyluric acid was not changed greatly the reaction of the urine but the amount of N-acetyl-PAS was greater when the urine was acid and smaller when alkaline. There was not difference in the amount of glucuronide and sulfate excreted in the case of salicylamide.