Anthelmintic Similarly, researchers have found that piperazine may also

Anthelmintic
drugs generally target the neuromuscular junction and the energy-generating
metabolism (Rew 1978). Piperazine (the
main types used are piperazine hydrate and piperazine citrate), introduced in
1953, was one of the most common and widely used drug against roundworms (Ascaris lumbricoides) and pinworms (Enterobius vermicularis). Toxicologically,
piperazine has an oral LD50 of 5g/kg in humans. Mechanistically, piperazine
hyperpolarizes nerve endings by blocking the worm muscle’s response to
acetylcholine, resulting in flaccid paralysis in these worms (Castillo et al. 1963; Sheth 1975; Norton
and DeBeer 1957). These paralyzed worms are then removed alive from the
intestinal lumen by peristalsis. However, many studies have suggested that
piperazine is a GABA receptor agonist, causing the opening of GABA-gated
chloride channels (Martin 1985; Harder
2002) Similarly, researchers
have found that piperazine may also function as a histamine receptor. Despite
this, this drug has since been discontinued (in 2012) due to the difficulty in
obtaining raw materials to produce piperazine. In addition, piperazine is known
to produce carcinogenic nitrosamines and to trigger sensitivity in the central
nervous system.