Fenbendazole is a broad spectrum benzimidazole anthelmintic used against gastrointestinal parasites including: giardia, roundworms, hookworms, whipworms, the tapeworm genus Taenia, pinworms, aelurostrongylus, paragonimiasis, strongyles, and strongyloides that can be administered to sheep, cattle, horses, fish, dogs, cats, rabbits, most reptiles, freshwater shrimp tanks as planaria and hydra treatments, as well as seals.
It is not effective against Dipylidium caninum, a common dog tapeworm.
Its mechanism of action is by binding to tubulin, a protein part of the microtubules in the cells of these parasites.
This binding to tubulin disrupts the microtubules’ formation and function, leading to the parasites’ inability to absorb nutrients, resulting in their eventual death.
This mode of action makes the drug effective against both adult and larval stages of many parasitic worms.
Fenbendazole is commonly used to treat intestinal parasites: roundworms, hookworms, whipworms, and certain tapeworms.
This drug often administered as part of a broader deworming protocol.
In equine medicine it is used to control strongyles, pinworms, and ascarids.
Drug interactions may occur if salicylanilides are co-administered: Abortions in cattle and death in sheep have been reported after using these medications together.
The appropriate dosage of fenbendazole depends on the specific animal species being treated as well as the formulation or preparation being used.
Fenbendazole is poorly absorbed from the gastrointestinal tract.
It is metabolized in the liver to oxfendazole, which is also anthelmintic, and partially gets reduced back to fenbendazole in the liver and rumen.
Studies show that it can act as a moderate microtubule destabilizing agent, causing cancer cell death by modulating multiple cellular pathways, including inhibiting glycolysis, down-regulating glucose uptake, inducing oxidative stress, and enhancing apoptosis.
Fenbendazole is not currently approved for use in humans, and its pharmacokinetics and safety profile in humans are not well-documented.
Despite promising preclinical data, further clinical trials are necessary to establish its safety and efficacy in human cancer therapy.