Thiabendazole
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| Thiabendazole structure |
It is the prototypical agent.It is approved for use in ruminants and horses.
Mode of action
Thiabendazole inhibits fumarates reductase,which catalyzes the formation of succinate from fumarate.Interference with succinate formation leads to the inhibition of adenosine triphosphate ATP formation.
Pharmacokinetics
Thiabendazole is lipid soluble.As a result of poor dissolution in digestive fluids thiabendazole may be poorly or erratically absorbed from the gastrointestinal tract.Metabolism occurs via hydroxylation and followed by conjugation.The 5-hydroxy metabolites are excreted as urinary glucuronide and sulfate,in cattle,excretion is complete within 3 days.
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| Side effect to vitro |
Clinical uses
- In ruminants, thiabendazole is effective against major gastrointestinal nematodes.It is not effective against whipworms,lung worms or filariae.
- In horses, thiabendazole is effective against strongyles, but large doses are needed to kill Strongylus vulgaris .It is not effective to treat intestinal thread worms and pin worms.
Adverse effects
Because fumarate reductase does not exist in mammals, thiabendazole is one of the safest antinematodal drugs.
Other benzimidazoles are;
- Albendazole
- Febendazole
- Mebendazole
- Oxfendazole