Is Fenbendazole Safe For Humans?

Ingesting fenbendazole is commonly used to treat parasitic worms in animals like horses and has been known to help some cancer patients. However, fenbendazole isn’t approved for use in humans, and it has been associated with several side effects. The anthelmintic drug is used in the food industry as a treatment for internal parasites of domestic animals such as pinworms, giardia, roundworms, hookworms, and Taenia solium. It is also used in an extra-label manner to treat Syngamus trachea, a parasitic nematode that causes disease in pheasants. While this treatment has been shown to be highly effective, few studies have been conducted to assess risks to humans.

A woman with advanced nonsmall cell lung cancer (NSCLC) began self-administering fenbendazole after reading social media reports that it was effective against her tumors. Nine months later, she developed severe liver injury. Physicians should ask patients about any self-administered substances that they have taken, including dietary supplements and herbs, and monitor them for potential adverse reactions.

To determine whether fenbendazole affected radiation sensitivity in cancer cells, fenbendazole was administered for 2 h to cultures of human cancer cell lines in a medium in which the concentration of oxygen was controlled. Cell viability was determined by measuring the number of viable cells in cultures treated with varying concentrations of fenbendazole. Regardless of the concentration, all survival curves had a similar shape, with a steep decrease in cell viability at low doses and a plateau on which cell numbers remained relatively constant up to the maximum dose that could be absorbed by the cells. fenbendazole for humans