The electrochemical oxidation of azithromycin was investigated in order to elucidate the mechanism for possible oxidative metabolic pathways in humans. Electrochemical studies were carried out by cyclic voltammetry and preparative scale electrolysis at glassy carbon electrodes. It was found that azithromycin undergoes anodic oxidation at one or both amine groups with the rapid follow-up chemistry of intermediate radical cation. Main products of the oxidation were determined by HPLC analysis and were identified as a protonated azithromycin and products obtained by demethylation of the 3'-dimethylamino or macrolactone amino group.