Absorption and Excretion of Drugs. XXVI. Effect of Water-Soluble Bases on Rectal Absorption of Sulfonamides

Abstract

The rates of absorption of sulfonamides were measured in the presence of a number of water-soluble bases. The absorption rates was reduced by these bases. This reduction depends mainly upon their decrease of lipid-vehicle partition. The differences existed in their absorption at incorporating the various water-soluble bases, and these differences are related to the dielectric constants of the bases: the larger their dielectric constant, the smaller the reduction of rectal absorption. The results suggest that the drug absorption in the presence of water-soluble bases can be interpreted by the depression of the polarity in the vehicle.