Mel Gibson Podcast Endorsement Drives Ivermectin Prescriptions Among Cancer Patients

Prescriptions for an antiparasitic drug combination spiked among cancer patients after actor Mel Gibson endorsed it as a cancer treatment on Joe Rogan's podcast in January 2025.

Gibson appeared on the episode and described three friends with stage 4 cancer. "All three of them don't have cancer right now at all," he said. Rogan asked what treatments they used, and Gibson replied, "Ivermectin, fenbendazole."

Ivermectin treats infections from certain worms and parasites in humans and animals. Fenbendazole, a veterinary drug for animal worms, belongs to the benzimidazole class, which includes albendazole, mebendazole and thiabendazole.

"I don't believe that there is anything that can afflict mankind that hasn't got a natural cure for it," Gibson added.

Researchers from Virginia Tech Carilion School of Medicine, UCLA and the University of Michigan examined health records of more than 68 million patients in ambulatory care settings. They looked for same-day prescriptions of ivermectin plus a benzimidazole after Gibson's appearance, which drew 60 million views in the month after airing.

Overall prescribing rates nearly doubled. Among cancer patients, rates rose 2.5 times. Increases were largest among men, White patients, those ages 18-64 and residents of southern states.

The study appeared Tuesday in JAMA Network Open. It did not examine safety outcomes of the drug combination. No clinical trials back ivermectin-benzimidazole for cancer treatment.

"Clinicians talk about how difficult it is when the patient demands or asks for a medication that they really feel passionately might help," said lead author Michelle Rockwell, a health services researcher at Virginia Tech. "And that's where I think these celebrity influencers really play a big role."

Some lab and animal studies show anti-cancer effects from the drugs, but doses for even small impacts would be toxic for humans, said Skyler B. Johnson of University of Utah Huntsman Cancer Institute.

Johnson raised concerns about ivermectin's impact on processing cancer treatments and other drugs.

The observational study could not prove Gibson's comments caused the prescription rise. Prescriptions ordered do not mean they were filled or taken. Some patients may have bought ivermectin without prescriptions from agricultural sellers. Cancer status might have been misclassified, and the study did not check if patients used the drugs with conventional treatment or as a substitute.