Conductive compositions whose electrical properties do not change significantly due when stored open to the atmosphere, methods for preparing the compositions, and medical electrodes that comprise the compositions are disclosed. The compositions are hydrogels that comprise about 33 wt% to about 68 wt% of a humectant or a mixture of humectants； about 1 wt% to about 8 wt% of an electrolyte or mixture of electrolytes； about 6 wt% to about 20 wt% of water； about 18 wt% to about 45 wt% of a copolymer. The copolymer comprises, in polymerized form, about 80 mol% to about 95 mol% of a first monomer, which is a mixture of acrylic acid and a salt thereof, about 5 mol% to 20 mol% of a second monomer, preferably a salt of 2-acrylamido-2-methylpropane sulfonic acid, and, optionally a crosslinking agent. The conductive composition has a pH of about 7.0 or less.
