Fenbendazole Explained

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Watchedfields:changed
Verifiedrevid:443623479
Iupac Name:Methyl N-(6-phenylsulfanyl-1H-benzoimidazol-2-yl)carbamate
Dailymedid:Fenbendazole
Cas Number:43210-67-9
Atc Prefix:P02
Atc Suffix:CA06
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Unii:621BVT9M36
Kegg:D04140
Chebi:77092
Chembl:37161
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Fenbendazole (also known as Fenben) is a broad spectrum benzimidazole anthelmintic used against gastrointestinal parasites including: giardia, roundworms, hookworms, whipworms, the tapeworm genus Taenia (but not effective against Dipylidium caninum, a common dog tapeworm), 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.[1]

Mechanism of Action

Fenbendazole works by binding to tubulin, a protein that is part of the microtubules in the cells of parasites. This binding disrupts the microtubules' formation and function, leading to the parasites' inability to absorb nutrients, resulting in their eventual death. This mode of action makes fenbendazole effective against both adult and larval stages of many parasitic worms.[2] [3]

Uses in Veterinary Medicine

Dogs and Cats

Fenbendazole is commonly used to treat intestinal parasites, including roundworms, hookworms, whipworms, and certain tapeworms. It is often administered as part of a broader deworming protocol. [4]

Horses

In equine medicine, fenbendazole is used to control strongyles, pinworms, and ascarids. It is available in paste form for easy administration.[5]

Cattle and Goats

Fenbendazole is effective against lungworms, stomach worms, and intestinal worms in ruminants. It is administered through feed, drenching, or bolus form.[6]

Drug interactions

Drug interactions may occur if salicylanilides such as dibromsalan and niclosamide are co-administered. Abortions in cattle and death in sheep have been reported after using these medications together.[7] Abortions in domestic ruminants have been associated with concurrent use of anti-trematode therapeutic agents.[8]

Dosage and Administration

The appropriate dosage of the medication fenbendazole depends on the specific animal species being treated as well as the particular formulation or preparation of the fenbendazole product being used. To ensure the correct dosage considering the animal species being treated with its weight, using a dosage calculator like the Fenbendazole Paraclear Defense Dosage Calculator would be recommended.[9] [10]

Toxicity

Fenbendazole is poorly absorbed from the gastrointestinal tract in most species. The in laboratory animals exceeds 10 g/kg when administered orally.[7]

Metabolism

Fenbendazole is metabolized in the liver to oxfendazole, which is anthelmintic too; oxfendazole partially gets reduced back to fenbendazole in the liver and rumen.[11] [12] Also, fenbendazole itself is an active metabolite of another anthelmintic drug, febantel.[13]

Safety and Precautions

Fenbendazole is generally safe when used as directed. However, it is important to follow veterinary guidelines and dosage instructions to avoid potential side effects. Some animals may experience mild gastrointestinal upset. It is not recommended for use in pregnant animals without veterinary advice.[14]

See also

Notes and References

  1. Web site: Fenbendazole: From MD Anderson to Joe Tippens . 2023-10-19 . Institute of Integrative BioOncology . en-US.
  2. Duan Q, Liu Y, Rockwell S . Fenbendazole as a potential anticancer drug . Anticancer Research . 33 . 2 . 355–362 . February 2013 . 23393324 . 3580766 .
  3. Dogra N, Kumar A, Mukhopadhyay T . Fenbendazole acts as a moderate microtubule destabilizing agent and causes cancer cell death by modulating multiple cellular pathways . Scientific Reports . 8 . 1 . 11926 . August 2018 . 30093705 . 10.1038/s41598-018-30158-6 . 6085345 .
  4. Web site: Fenbendazole (Panacur®, Safe-guard®) for Dogs and Cats . 2024-07-01 . www.petmd.com . en.
  5. Web site: What Is Fenbendazole and Is FenCare Right for My Horse? Farnam . 2024-07-01 . www.farnam.com . en.
  6. Web site: Fenbendazole .
  7. Book: Plumb DC . Plumb's veterinary drug handbook . 2005 . PhrmaVet . Stockholm, Wis. . 978-0-8138-0518-4 . Fifth .
  8. Sarangi LN, Tharani N, Polapally S, Rana SK, Thodangala N, Bahekar VS, Prasad A, Chandrasekhar Reddy RV, Surendra KS, Gonuguntla HN, Ponnanna NM, Sharma GK . Infectious bovine abortions: observations from an organized dairy herd . Brazilian Journal of Microbiology . 52 . 1 . 439–448 . March 2021 . 33415719 . 7966683 . 10.1007/s42770-020-00414-x .
  9. Web site: 2023-04-10 . Fenbendazole (safe-Guard) dosing calculator . 2024-07-01 . UK Aquatic Plant Society . en-GB.
  10. Web site: Fenbendazole (ParaClear Defense) Dosage Calculator 10% Solution . live . 1 July 2024.
  11. Web site: Fenbendazole, Anthelmintic for Veterinary Use on Cattle, Sheep, Goats, Pig, Poultry, Horses, Dogs and Cats Against Roundworms and Tapeworms . Junquera P . 2015-07-26 . PARASITIPEDIA . 2015-09-08.
  12. Web site: Oxfendazole, Anthelmintic for Veterinary Use on Cattle, Sheep, Goats, Horses, Dogs and Cats Against Roundworms and Tapeworms . Junquera P . 2015-07-26 . PARASITIPEDIA . 2015-09-08.
  13. Web site: Febantel for Veterinary Use on Dogs, Cats, Cattle, Sheep, Goats, Pig and Poultry Against Roundworms and Tapeworms . Junquera P . 2015-07-26 . PARASITIPEDIA . 2015-09-08.
  14. Web site: Prescription Label . live . 1 July 2024.