Abstract: A region to be anesthetized is connected between a pair of electrical leads. A train of like primary direct-current pulses of a polarity tending to counter nerve-generated pain signals is applied to the region by the conductors. Between these primary pulses there is applied to the region to be anesthetized direct-current secondary voltage pulses of a polarity opposite that of the primary pulses and of duration and current strength equal to only a fraction of the duration and current strength of the primary pulses. The primary and secondary pulses are both of constant current and the primary pulses have a current strength and duration equal to between 3 and 20 times the current strength and duration of the secondary pulses. A timer or clock operates a relay which serves to reverse the polarity of the voltage applied to the region to be anesthetized and to alternately connect it to either of a pair of current regulators in turn connected to a battery power supply.