As an antiparasitic, it is capable of treating roundworms, hookworms, and other kinds of helminth species that can attack wild animals, livestock and humans. It also has effects of inhibiting the angiogenesis of cells. The mechanism of action is still not fully understood. It has found that Thiabendazole is capable of suppressing the helminth-specific mitochondrial enzyme fumarate reductase, further inhibiting the citric acid cycle, mitochondrial respiration and ATP production, leading to helminth's death. It may also inhibit the microtubule polymerization processes.