There is no peer-reviewed evidence that fenbendazole, which is used to treat parasites in dogs, can cure cancer in humans. However, this anthelmintic is being widely promoted as an alternative cancer treatment online, including on social media platforms like TikTok and Facebook. Despite being sold as an effective antiparasitic medicine, Health Canada lists fenbendazole for veterinary use only and is not approved for human consumption.

The benzimidazole carbamate anthelmintic drug fenbendazole is known to have broad-spectrum antiparasitic activity and to inhibit growth of cancer cells. This is due to its ability to block proteasomal degradation and disrupt microtubule formation in cancer cells. In addition, fenbendazole also exhibits the ability to interfere with GLUT4’s linear movement through microtubules and to significantly decrease insulin-fueled sugar absorption.

A 2-h treatment with fenbendazole was not toxic to aerobic EMT6 monolayer cultures at concentrations up to the limit of solubility. A 24-h treatment of these cells with fenbendazole resulted in significant decreases in the number of viable cells and clonogenicity. This effect was independent of the p53 status of cells.

A 5-FU-resistant CRC cell line (SNU-C5/5-FUR) exhibited a higher IC50 value for fenbendazole than wild-type cells. In this cell line, fenbendazole induces cell death by both enhancing p53-independent apoptosis and by inducing ferroptosis-augmented apoptosis. Unlike 5-FU, fenbendazole induces these responses without inducing cell cycle arrest or necroptosis in these cells. These results suggest that fenbendazole may be an alternative to current therapies for the treatment of 5-FU-resistant CRC. fenben lab fenbendazol