Pyrantel is an antinematodal thiophene

Thiophene

Thiophene is a heterocyclic compound with the formula C4H4S. Consisting of a flat five-membered ring, it is aromatic as indicated by its extensive substitution reactions. Related to thiophene are benzothiophene and dibenzothiophene, containing the thiophene ring fused with one and two benzene...

. It is often prescribed by veterinarians to treat and prevent the occurrence of intestinal parasites in small animal pets.

Mechanism of Action

Pyrantel is a nicotinic receptor agonist . Like levamisole

Levamisole

Levamisole is an anthelminthic and immunomodulator belonging to a class of synthetic imidazothiazole derivatives. It was discovered at Janssen Pharmaceutica in 1966...

 and the related pyrimidine

Pyrimidine

Pyrimidine is a heterocyclic aromatic organic compound similar to benzene and pyridine, containing two nitrogen atoms at positions 1 and 3 of the six-member ring...

 morantel, it can elicit spastic muscle paralysis

Paralysis

Paralysis is loss of muscle function for one or more muscles. Paralysis can be accompanied by a loss of feeling in the affected area if there is sensory damage as well as motor. A study conducted by the Christopher & Dana Reeve Foundation, suggests that about 1 in 50 people have been diagnosed...

 in parasitic worms due to prolonged activation of the excitatory nicotinic acetylcholine (nACh) receptors

Nicotinic acetylcholine receptor

Nicotinic acetylcholine receptors, or nAChRs, are cholinergic receptors that form ligand-gated ion channels in the plasma membranes of certain neurons and on the postsynaptic side of the neuromuscular junction...

 on body wall muscle

Muscle

Muscle is a contractile tissue of animals and is derived from the mesodermal layer of embryonic germ cells. Muscle cells contain contractile filaments that move past each other and change the size of the cell. They are classified as skeletal, cardiac, or smooth muscles. Their function is to...

. This has been studied in body wall muscle preparation of the parasitic nematode Ascaris

Ascaris

Ascaris is a genus of parasitic nematode worms known as the "giant intestinal roundworms". One species, A. suum, typically infects pigs, while another, A. lumbricoides, affects human populations, typically in sub-tropical and tropical areas with poor sanitation. A...

.