Fenbendazole is an anthelmintic drug used to treat parasites in animals. Although some preclinical studies are examining it and other drugs in the same class as possible cancer treatments, there’s no evidence to show that they can cure human cancer.

A video circulating on TikTok and Facebook claims that the dog wormer ingredient fenbendazole can cure cancer. While it’s true that the drug can suppress cancer cells in test tubes and in mice, there isn’t enough proof that it can also do so in people.

The drug works by stopping the proper growth of microtubules, which are a kind of framework for all cells and provide structure to them. Researchers have discovered that some cancer cells have abnormally shortened microtubules. The drug can prevent the growth of these microtubules, and some tumours shrink as a result.

But, as a 2021 press release from Johns Hopkins Medicine noted, “The results of this study do not suggest that fenbendazole will reduce the progression of pancreatic cancer in humans. Rather, they support our previous findings that other antiparasitic medications, such as metronidazole and benzimidazole carbamate, which are related to fenbendazole, may be effective in reducing the progression of pancreatic cancer.”

To see whether fenbendazole could reduce cancer growth in vivo (in living people), researchers treated tumour-bearing mice with the drug every second day for 12 days. When they weighed the mice after the treatment period, they found that the tumours had significantly reduced in size and weight. In addition, the researchers noticed that fenbendazole caused a partial alteration of the network of microtubules that supports cancer cells, and increased cell death via p53-mediated apoptosis in both wild-type (WT) and mutant p53 colorectal cancer cells. fenbendazole for cancer