How Does Ovex Work? Ovex tablets are used for the treatment of threadworm in adults & children. Threadworm is caused through poor personal hygiene & consists of tiny parasitic worms that infect the large intestine of humans. They are most common in young children but anyone of any age can become infected. Ovex contains Mebendazole. Mebendazole works by preventing the threadworms from absorbing glucose (sugar), which results in the threadworms dying off within a few days. It does not kill the eggs, which is why treatment needs to be continued for as long as it takes to successfully treat the infection. How To Take Ovex Adults & children over 2 years of age: 1 tablet to be chewed or swallowed whole. Pregnant or breastfeeding mothers should not take this product & should seek medical advice.