I have been taking fenbendazole once a week for a few weeks now, the first week I passed a rope 3ft long, lots of others also they look just like the ones in your pictures. Have you any idea where these things originate from, I have not left uk for many years prior to getting these so drs say I cant have parasites! I have found the same as you that the critters seem to become immune to the meds & you have to keep changing them as they find ways of protecting themselves &/or hiding. Keep up the good work. One day we will find a cure, with or without drs help. x