The electrochemical behavior of 12 non-steroidal anti-inflammatory drugs (NSAIDs) was studied by means of cyclic voltammetry at a glassy carbon electrode. The underlying solvent had a considerable effect to the oxidation potentials of the investigated NSAIDs due to the alteration of their polar intermediates’ solvation. Oxicams were more capable of electrochemical oxidation, and the influence of both specific and non-specific solute–solvent interactions in their reactivity was confirmed by means of Kamlet–Taft’s analysis. Oxicams were further studied by chronoamperometry at the potentials of 300, 500, and 800 mV. The results obtained by the employed electroanalytical techniques were compared with the reactivity of oxicams towards 1,1- diphenyl-2-dipicrylhydrazyl (DPPH). The study showed a correlation of oxicams’ amperometric signal at 800 mV with their absolute reaction rate, z with DPPH.