Effects of macromolecular additives and urea on the intestinal absorption of acetaminophen in rats.

Abstract

The effects of sodium carboxymethylcellulose (CMC), sodium arginate (SA), methylcellulose (MC) and polyvinylpyrrolidone (PVP) on the intestinal absorption of acetaminophen in situ were investigated in rats. Among the macromolecular additives, only PVP exhibited an inhibitory effect on drug absorption. Studies in vitro (solubility and dialysis experiments) showed that there is an interaction between acetaminophen and PVP. The inhibitory effect of PVP on the intestinal absorption of acetaminophen was suppressed by the addition of urea. Dialysis data showed that urea tends to reduce the binding between acetaminophen and PVP.