Description
Wormentel (Fenbendazole) 150 mg – 10 tablets
Wormentel is presented as a veterinary fenbendazole tablet product. Fenbendazole is a benzimidazole anthelmintic used in animal health to control susceptible parasitic worms, with the exact approved uses depending on the species and formulation.
Active Ingredient and Medicine Class
The verified active ingredient is fenbendazole, an anthelmintic in the benzimidazole class. Medicines in this group are widely used in veterinary practice against gastrointestinal nematodes and, in some labeled products, certain tapeworms.
Established Medical Uses
Established veterinary uses of fenbendazole include the treatment and control of susceptible gastrointestinal parasites in animals. Depending on the product label and target species, these may include roundworms, hookworms, whipworms, and some tapeworms. Labeled indications are not interchangeable between animal species, and a specific brand or tablet formulation should not be assumed to have the same approved uses as another fenbendazole product.
How It Works
Fenbendazole works by interfering with parasite microtubules, which are structures the worm needs for normal cell function and survival. This disrupts essential processes in the parasite and leads to its death or removal from the animal.
Important Safety Information
Fenbendazole is for veterinary use, and product labeling may include species-specific restrictions. Safety warnings can differ by formulation, but important concerns commonly include use only in the intended animal species, attention to parasite resistance, and caution in pregnant or lactating animals where the label restricts use. Extra-label or prolonged use in dogs has been associated with serious blood-related adverse events, including bone marrow suppression and pancytopenia. Fenbendazole should not be assumed to be safe for human use.
Possible Side Effects
Reported adverse effects in animals are often mild, and may include vomiting or gastrointestinal upset. More serious reactions are uncommon but can occur, especially with inappropriate or extra-label use. In dogs treated longer than labeled durations, reported adverse events have included severe bone marrow effects. As with any veterinary anthelmintic, ongoing symptoms after treatment may indicate incomplete parasite control or another underlying problem.
Scientific Evidence
Veterinary studies support fenbendazole’s anthelmintic activity against susceptible parasites in animals. A controlled clinical study in dogs found fenbendazole effective for naturally acquired giardiasis, while also confirming activity against several labeled canine intestinal parasites. More recent review literature continues to describe fenbendazole as a veterinary benzimidazole with established antiparasitic use, while also noting that human safety and efficacy data are not adequate to support use outside research settings.
Medical Information Notice
This page is an educational summary based on sources available at the time of review. It does not replace the official product leaflet, veterinary prescribing information, or an individual assessment by a qualified professional.
Medical Sources
- U.S. Food and Drug Administration / DailyMed SAFE-GUARD fenbendazole granule: official animal drug label
- U.S. Food and Drug Administration Dear Veterinarian Letter regarding adverse events associated with extra-label use of fenbendazole in dogs
- Carolyn Cray et al. An Update on the Biologic Effects of Fenbendazole. Comp Med, 2022. View scientific article
- Jolie Nguyen et al. Oral Fenbendazole for Cancer Therapy in Humans and Animals. Anticancer Res, 2024. View scientific article
- S C Barr et al. Efficacy of fenbendazole against giardiasis in dogs. Am J Vet Res, 1994. View scientific article
