Pharmacokinetic Studies of Suplatast tosilate (IPD-1151 T) (I) :Absorption, Distribution and Excretion after Administration of 14C-Suplatast tosilate (IPD-1151T) to Rats.

The absorption, distribution and excretion of suplatast tosilate, (•})-[2-[4-(3-ethoxy-2-hy droxypropoxy)phenylcarbamoyl]ethyl ]dimethylsulfonium ‚•-toluenesulfonate (IPD-1151T) were studied in rats after a single or repeated administration of 14C-labeled-IPD-1151T. 1. After oral administration, the blood radioactivity reached the Cmax at 8hr and then decreased with half-life of 12day, and the blood-to-plasma level ratio became high. It seems that elmination of radioactivity from blood cell was very slow. It is suggested that absorption of IPD-1151T was affected by food as manifested by the decrease of blood radioactivity in fasting rats. 2. Approximately 87% and 11% of radioactivity was excreted during 72hr after intravenous administration in urine and feces, respectively and corresponding values for oral administra tion were approximately 26% and 73% in urine and feces. 3. About 9 % and 17% of radioactivity was excreted in bile after intravenous and oral administration, respectively. When the bile was administered, more than 90% of radioactivity