Effect of Phenacetin on the Uptake and Elimination of Salicylate by the Rat

Abstract

The blood levels of ¹⁴C, emanating from ¹⁴C-acetyl-salicylic acid (¹⁴C-ASA) p.o. and ¹⁴C-salicylic acid i.v., were decreased and unchanged, respectively, by the concomitant oral ingestion of phenacetin. Subsequent investigation showed that phenacetin: (a) did not affect the total renal excretion of ¹⁴C or ASA metabolites; (b) enhanced the retention of ¹⁴C, from either ¹⁴C-ASA or ¹⁴C-phenacetin, in the stomach contents and stomach tissues; (c) delayed stomach emptying, and (d) did not form undialyzable or insoluble complexes with ASA. It was concluded that phenacetin reduced the blood levels of salicylate by inhibiting stomach emptying.