I'm an engineer, so i've got a couple of alternatives.
zap with electrodes so that the current passes through the part you are trying to zap. Try your left foot to your right arm or right foot to left arm.
Alternatively and this is out there, but use a a rectally inserted electrode. You would probably want to turn the voltage down for this. then use the other electrode in one hand. Try swapping hands too. start with a dry electrode and work your way up in case there is too much current. if you use a silver electrode you may make some Colloidal Silver at the same time :) bonus.