hi..you should consider several thinks:
as if paresits are adapted to medical drug. 2 - you should fight them from 2 front line : avoid having eggs and avoid retroinfection by hatching the eggs in anuse or rectom..by using suppository , cream on anuse and even enema...3- I have an theory that the pinworm have found a safe place in intestin to survive...and it can be the appendix...check yourself for this ..by sonography or other medical diagnose divice...let me know on : +98 912 1932738 by telegram