Hi & Welcome to HCM. I appreciate your concern for the recurrent thread worm infection. As such there is documented evidence of these worms developing resistance, it is likely that either you have not taken the taken properly or strict hygiene measures not being followed. The treatment involves two doses of Mebendazole or Albendazole with the second dose being given 2 weeks after the first dose. All your family members and other close contacts should be treated at the same time. Because itching and scratching of the anal area is common in thread worm infection, reinfection can occur easily so good hand hygiene is essential which can be achieved by the following measures: 1. Appropriate handwashing (particularly before eating or handling food, after using the toilet, and after changing a diaper) 2. Keeping the fingernails clean and short 3. Avoiding fingernail-biting 4. Avoiding scratching the skin around the anus 5. Daily morning bathing removes a large proportion of eggs; showering may be preferred to avoid possible contamination of bath water. 6. Careful handling and frequent changing of underclothing, night clothes, towels, and bedding can help reduce infection, reinfection, and environmental contamination with threadworm eggs. These items should be laundered in hot water, especially after each treatment. Hope to have answered your query. A feed back is appreciated.