I have been treated for pinworms with vermox for 8 weeks now (4 dosages), but the itching - so i suppose the worms still won't go away. i have short and clean nails, wasing my hands very frequently, cleaning, washing, etc. why won't it end?

If it was diagnosed pinworm and not empiric treatment there is possibility of reinfection because the eggs could survive for 2 to 3 wks on clothing, surfaces; and breathing it in may even set up reinfection. There are also other causes of itching like hemorrhoids, yeast infection; and you may require reevaluation See: http://my.clevelandclinic.org/health/diseases/15574-anal-itching-pruritus-ani.