Effect of cephalexin and tetracycline on galactose absorption in rat small intestine.

The effects of cephalexin and tetracycline HCl on D-galactose absorption in rat small intestine were investigated. Both antibiotics inhibited D-galactose uptake into isolated intestinal mucosa in a dose-dependent fashion. In vivo studies showed that cephalexin and tetracycline HCl reduced D-galactose absorption and that the transport defect was not reversible on cessation of antibiotic perfusion. Both the active and passive components of D-glactose absorption were inhibited by the antibiotics tested. Furthermore, both drugs reduced mucosa O2 consumption and inhibited D-galactose absorption when they were perfused in a contiguous loop. We conclude that the diminished D-galactose transport by rat small intestine after tissue exposure to either cephalexin or tetracycline HCl appears to be in part due to an insufficient energy supply.