Is there a Fenbendazole/ivermectin protocol for persistent/scattered pinworm infestations? Iím in Canada and canít get Albendazole or Mebendazole. I took the Fenbendazole for a few days and had a really bad reaction so I stopped. Maybe I was taking too much but itís a powder so hard to dose. I had tunnel vision and was very dizzy/lightheaded and had very bad insomnia, was only able to sleep an hour or 2 a night. Everything I have read says there is minimal side effects.