How does Benzimidazole function against helminths?

Benzimidazoles function against helminths primarily by inhibiting microtubule polymerization, which is essential for various cellular processes in the parasites. These agents bind to the beta-tubulin subunit of tubulin, preventing its assembly into microtubules. Microtubules are critical for maintaining the structure of the cell, enabling cellular transport, and facilitating mitotic processes. By disrupting microtubule formation, benzimidazoles effectively impair the helminth's ability to absorb nutrients and reproduce, ultimately leading to the parasite's death.

The specificity of this mechanism also accounts for the relative safety of benzimidazoles in humans, as microtubule structures in human cells are not as affected by the drug compared to those in the helminths. This explains why they are widely used as an effective treatment for various helminthic infections.