Hi, thanks for asking in Healthcare Magic.
Thread worms means Enterobius sp. in UK and Stongyloids sp. in USA. Re infection is a common problem with both these worms. The eggs of Enterobius survive for more than two weeks and develop in to larva to cause re infection. Auto (self) infection is a problem in Strongyloids and result in persistent infection. Stool examination will help in identifying the type of worm.
Ovex or
Mebendazole results in nearly 100% cure rate against Enteobius but has a high failure rate in Strongyloids infection.. But the lethal action of Mebendazole on worms is slow and it takes 2 to 3 days for complete action. As repeated infection is always a problem with Enterobius single dose is not sufficient. For Enterobius the dose should be repeated once more after 2 to 3 weeks to kill the ova that develops later.
Ivermectin is indicated as the first line drug in Strongyloids infection.
But, the drug of choice in both these worm infestation is
Albendazole. For Enterobius a single dose of 400 mg followed by one more dose after 3 weeks is sufficient for 100% cure. For Strongyloids, 400 mg daily for 3 consecutive days followed by a second course repeated after 3 weeks.
In case of
Enterobius infection, your boy friend also should be treated as the eggs laid by the worm around anus can be passed through direct contact and can cause infection in him.
I hope this is useful to you.