What do you do if you don't want to take medication for parasites?

I know I have some kind of roundworm, I can feel them all over my body, seen a few in my stool.

The forum posts I keep seeing seem to all say that herbs are not going to be enough to kill these things and I will need to self medicate with chemicals.

Is this true? I'm really, really scared of taking chemical meds like fenben and such.