The work is devoted to the problem of the Gaussian white noise influence on a canard cycle in a dynamic model of an electrochemical reaction. This study is conducted on the example of an electrochemical reaction of the Cooper-Slyter type. An analysis of noise-induced transitions was performed, the effect of external disturbances on the limit cycle is investigated, the sensitivity of the cycle to the noise is found. A critical noise intensity, at which the small-amplitude oscillations are transformed into mixedmode oscillations, is obtained. It is shown that an increase in the intensity of random perturbations can lead to significant deformations of the modes in the model up to their destruction.