fenbendazole wormentel 10 % veterinary oral paste (often 10% concentration) is a broad-spectrum anthelmintic used to treat and control internal parasitic infections in dogs, cats, horses, and livestock. Dogs & Cats: Treats gastrointestinal parasites and, in some cases, Giardia, often administered for 3–5 consecutive days. Horses/Equine: Controls large/small strongyles, pinworms, and ascarids (roundworms).Livestock: Used for cattle and sheep to manage lungworms and gastrointestinal nematodes.