A processor implemented nerve stimulation system for regional anesthesia administration varies pulse width as a programmed function of applied current or varies applied current as a function of adjusted pulse width. The system also provides a waveform of repeating cycles of different pulse width components separated within the waveform frequency and which may be simultaneously attenuated as a function of applied current within an attenuation range. Among possible functional relationships between pulse width and applied current within an attenuation range is the exponential reduction of pulse width as a function of applied current.