I think it's important to always remember that one person's experience is not universal
In other words one person can have a parasite infection that IS cleared up by using a zapper; while another person can have a parasite infection that will stubbornly resist being cleared up by a zapper
who knows what the variables are here? perhaps it depends on the kind of parasite, the amount of time the infection has been occurring, how an individual body response to electric therapy, etc. etc.
By the way, when did you taze yourself? Was that recently? That sounds pretty intense