Damage from Electrostatic Over-Stress (EOS) to shielded anisotropic magnetoresistive (AMR) sensors used for magnetic tape storage devices were studied using square wave voltage pulses. Changes to the sensor's physical and magnetic properties were measured after each of a number of sequential pulses. The change in sensor resistance and magnetic amplitude and asymmetry were each fit to a thermodynamic model. Two processes were observed: Annealing and degradation, with respective activation energies of 2.1plusmn0.1 eV and 2.9plusmn0.1 eV. The annealing was associated with a slight decrease in sensor resistance and an increase in AMR asymmetry. The degradation was associated with a decrease in AMR asymmetry and amplitude, and an increase in sensor resistance.