Multidrug efflux pump that functions as a H(+)/organic cation antiporter. Mediates the efflux of cationic compounds, such as the model cations, tetraethylammonium (TEA) and 1-methyl-4-phenylpyridinium (MPP+), the platinum-based drug oxaliplatin or weak bases that are positively charged at physiological pH, cimetidine, the platinum-based drugs cisplatin and oxaliplatin or the antidiabetic drug metformin. Mediates the efflux of endogenous compounds such as, creatinine, thiamine and estrone-3-sulfate. Plays a physiological role in the excretion of drugs, toxins and endogenous metabolites through the kidney. {ECO:0000269|PubMed:16807400, ECO:0000269|PubMed:16914559, ECO:0000269|PubMed:17509534, ECO:0000269|PubMed:19158817, ECO:0000269|PubMed:21419862}. [Isoform 6]: Non-functional protein. . This is the function of Ensembl gene identifier ENSG00000180638 (SLC47A2, solute carrier family 47 member 2).