Pinworms are really hard to get rid of, so i have heard from others. Cimber38 had plentiful parasites also pinworms. What she/he said is pyrantel pamoate worked well (several days in the row in the evening) followed by lots of enemas. Pyrantel is simply reese's pinworm medicine, the box has instructions for your weight (no need to take more). What others suggested for the itch was vicks vapo rub cream topically. They can return though so you will need to repeat it. And of course you need to be careful with the eggs on bed linen and clothing, and steam clean while you treat them. But i guess you already know that. I have been suggested to take the ivermectin paste along w pyrantel, in case something bigger would want to migrate out of the intestines. Ivermectin should paralyse roundworms for a while. It also kills the babies. I understand you prefer the herbal approach, but this stuff works, in case you want to try. You can try to apply some ivermectin paste on them, see what that does. If you have hemorrhoids then somethng gentle is better. Maybe some zinc oxide cream should also work. And do these along with the pyrantel and enemas.
No they do not contribute to anything apart from being a pain in the ass, literally. Hence the name parasite.