I had a pinworm problem a few years ago and found that various enemas really helped. At that time I think I was big into garlic enemas. (Though ACV, coffee, and probiotic plain organic yogurt would be good too). I just crushed 2 or 3 cloves of garlic and steeped them in hot water for anywhere from 10-30 minutes. strained the debris and used the cooled down water in the enema. 3 cloves might be a bit strong though but it really cleans out the gut :)
Colonics are super helpful for the whole body system but specifically for the pinworms, I'm not sure... maybe if the place you get the colonic
at offers "infusions" of certain antiparasitic herbs might be effective.
good luck :D.