Prescriptions for ivermectin and benzimidazole, an unproven cancer treatment, more than doubled in early 2025 after actor Mel Gibson endorsed the medicines on Joe Rogan’s podcast, according to researchers.
During the January 2025 episode, which has more than 13 million views on YouTube, Gibson spoke of three friends who had been battling stage-four cancer until they took ivermectin and fenbendazole, part of the class of drugs that includes benzimidazole. Ivermectin is an approved drug for treating parasitic infections in humans and animals, while fenbendazole is not approved for human use.
After these comments, cancer patients were prescribed the drugs at a rate 2.5 times higher in the first seven months of 2025 than in the same period in 2024, according to a study published in JAMA Network Open. Prescriptions of the drugs to all patients doubled during this window.
The researchers, who analysed health records for more than 68 million patients, warned that patients may delay or forgo conventional treatments in favour of unproven therapies. The spike was especially pronounced in white patients, men, and patients in the South, groups that overlap strongly with Rogan’s listenership.
In recent years, ivermectin became popular on the right for people seeking protection against Covid, and Rogan himself touted the drug, which is not an effective coronavirus treatment. Preclinical studies have suggested a potential anticancer benefit, but clinical trials are ongoing and it remains far from a proven cancer treatment for humans.
The study’s researchers noted the challenges of providing solid medical information in the age of influencers and AI. Half of U.S. adults under 50 get health and wellness information from influencers or podcasters, many of whom lack a scientific or medical background, according to a recent Pew Research report.
