Solute transporter for tetraethylammonium (TEA), 1-methyl-4-phenylpyridinium (MPP), cimetidine, N-methylnicotinamide, metformin, creatinine, guanidine, procainamide, topotecan, estrone sulfate, acyclovir, and ganciclovir. Responsible for the secretion of cationic drugs across the brush border membranes (By similarity). Belongs to the multi antimicrobial extrusion (MATE) (TC 2.A.66.1) family.