The anecdotal story of Joe Tippens, who says he beat advanced liver cancer by taking something you give dogs for worms, has left medical experts scratching their heads. But it’s not because of the dog dewormer itself. It’s what he did with it.
The drug is fenbendazole, commonly known as FZ. It is used in veterinary medicine to treat a variety of parasitic worms including whipworms, hookworms, and one species of tapeworm (Taenia pisiformis) in both humans and animals. It also treats other intestinal infections by cutting off the worms’ supply of nutrients.
FZ is a benzimidazole carbamate, a type of antiparasitic medication. While some preclinical research examining this class of drugs as potential anticancer treatments is underway, there is insufficient evidence that fenbendazole can cure cancer in humans.
According to the research, fenbendazole is thought to stop cancer cells from growing by blocking the growth of microtubules. Microtubules provide structure to all living cells, and targeting them is a common treatment strategy in cancer.
But it isn’t just fenbendazole that has people thinking about dewormer for cancer; other drugs in the same family, such as albendazole and mebendazole, are being promoted by patients as a treatment for their own cancers. Some of these patients are even using FZ together with standard cancer treatments like chemotherapy and radiation.
Experts like Prescott say this approach could be dangerous. These medications suppress the immune system, so combining them with immunotherapy can make it harder for the body to fight off disease. This can lead to side effects such as diarrhea, headaches, and fatigue.