Fenbendazole is a commonly used anti-worm medication in dogs and cats. It is also prescribed to ruminants to treat the trematodes that are associated with gastrointestinal disease (Giardia spp, Heterobilharzia americana, and Platynosomum fastosum). It presents exclusive action as an anthelmintic, not altering the organic functioning of the host. It acts by binding to b-tubulin and destroying its function. It induces cell death through several mechanisms.
A female dog with metastatic liver cancer was diagnosed in July 2019 by ultrasound and CT scan. Her CEA levels were increasing. She was given pembrolizumab monotherapy, but it did not improve her symptoms or prolong survival. She was told that she had a terminal prognosis. The patient decided to purchase oral fenbendazole, a dog deworming medication, on the internet as a treatment for her cancer. She was interviewed by veterinarians and she reported that she had seen videos on TikTok and Facebook that touted fenbendazole as a cure for cancer.
The fenbendazole was purchased from a website called fenben labs, which claimed to sell laboratory tested and verified fenbendazole. After requesting legitimate third party lab tests, it was found that the fenbendazole sold by fenben labs is actually just a low grade generic. It is manufactured in lithuania and held by a shell corporation that claims it has an independent lab testing their products. When compared to a commercially available brand, it was found that the fenbendazole from fenben labs had significantly less cytotoxic effects on human cancer cells. fenben lab fenbendazol