Drug-induced change in the distribution of sulfonamides in the mother rat and its fetus.

The distribution of a highly bound antibacterial sulfonamide was markedly altered in both the mother rat and its fetus by interfering with the binding of this drug to plasma protein in the mother. This effect was due to binding displacement, since the displacing agent had little or no effect on the distribution of another sulfonamide with very low binding to plasma protein.