What is the mechanism of action for anthelmintic drugs explained by a nurse?

Anthelmintic drugs primarily function by targeting specific metabolic pathways that are unique to helminths (parasitic worms). This is crucial because it allows the medications to disrupt the normal physiological processes of the worms without significantly affecting the host's own metabolic functions. For instance, some anthelmintics may inhibit the synthesis of important molecules that the worms need to survive or replicate, leading to their eventual death or inability to reproduce. This direct action on the worm's metabolism is vital for the effectiveness of these drugs, enabling them to selectively eliminate the parasites while minimizing harm to the host organism.

The other options do not accurately represent the primary mechanism of action of anthelmintic drugs. For example, while the host's immune response can play a role in fighting off infections, anthelmintics typically act directly on the worm itself rather than modifying the immune system's response. Similarly, merely increasing gastrointestinal motility or altering the gut's pH may help in expelling worms but is not the main way that these drugs achieve their anthelmintic effects.