Can common deworming drugs cure cancer?

In a January 2025 Joe Rogan Experience podcast, Mel Gibson shocked listeners when he told Rogan that three of his friends were cured of stage four cancer after taking the antiparasitic drugs ivermectin and fenbendazole. The podcast garnered more than 60 million views across multiple media platforms. As a result, prescriptions for the dynamic deworming duo skyrocketed.

Following the surge in prescriptions, health experts voiced concern, cautioning that scientific evidence does not support the use of fenbendazole or other antiparasitic drugs for cancer therapy. They warned that abandoning established cancer treatments in favor of unproven, celebrity-endorsed dewormers could have dire consequences.

Gibson’s remarks and the resulting backlash from health experts piqued my curiosity. Is it true? Could these common drugs be the cancer-curing miracle we’ve been looking for, or are they just snake oil that puts people in danger of losing ground in their battle against the disease?

After looking into the latest research, it appears the answer to that question remains to be seen, as studies investigating ivermectin and fenbendazole for cancer treatment are mostly preclinical research using petri dishes and animal models. However, these lab experiments have yielded interesting results. For example, a recent study published in Frontiers in Pharmacology found that fenbendazole suppressed breast cancer growth in mouse cells by altering cell metabolism and inducing pyroptosis, an inflammation-related form of cell death. In lab and animal studies, ivermectin inhibited several types of cancer, including breast, colorectal, kidney, and ovarian cancer.

Findings like these can get people excited, especially when a drug wipes out bad actors like cancer in a test tube or a mouse. But what happens in a lab dish or rodent can be wildly different than what happens in the human body. So, despite these promising lab findings, there’s still a glaring lack of rigorous, large-scale clinical trial data confirming that deworming medications destroy cancer cells in humans.

However, in April of this year, researchers published the results from an observational study involving real-world cancer patients who were prescribed ivermectin and mebendazole, a cousin of fenbendazole approved for use in humans. The participants took compounded oral capsules containing 25 mg ivermectin and 250 mg mebendazole. Some participants underwent chemotherapy, radiation, or surgery in addition to taking the antiparasitic drugs.

Among the 122 participants who completed the follow-up survey, nearly half reported tumor regression or no current evidence of disease, meaning some were cancer-free. Side effects were minimal, as only 25 percent reported mild stomach-related issues.

Although the study was observational and participants self-reported their outcomes, which may limit definitive conclusions, the researchers said the findings are compelling, and these well-tolerated drugs may offer therapeutic benefit for people with cancer.

Since the research so far looks promising, I can understand why some people with cancer might seek out these drugs. However, since they aren’t a proven cancer treatment and not FDA-approved to treat the disease, availability is limited, and access to them can be challenging.

During Rogan’s podcast, both Rogan and Gibson discussed possible reasons why these drugs weren’t widely available. Rogan said the FDA’s resistance to investigate alternative treatments is purely about money. Gibson added that there’s an agenda—Big Pharma wants to keep people on revenue-generating medications and doesn’t want a surefire cure for anything.

Nonetheless, in some states, such as Texas, Tennessee, Arkansas, Idaho, and Louisiana, ivermectin is available for sale over the counter or behind the counter. Elsewhere, compounded forms require a prescription, typically from integrative or functional medicine doctors. The problem is that not all pharmacies will honor these prescriptions.

Ivermectin is also an ingredient in some horse and livestock dewormers. However, using these products is dangerous as they often contain inactive ingredients that have not been evaluated for human consumption. They are also designed for livestock weighing up to 1,500 pounds, making it extremely easy for a human to overdose. This is precisely what happened during the pandemic after a study showed ivermectin killed SARS-CoV-2 in a petri dish within 48 hours. The findings, which also sparked a surge in ivermectin use, were later shot down by human studies, which found it was not effective as a treatment for the disease.

Shortly after the “ivermectin kills SARS-CoV-2” study dropped, ivermectin overdose cases surged in the U.S., mostly driven by the use of horse and livestock dewormers. So, tempting as it may be, don’t take animal dewormers from your local farm supply store. It’s just not safe.

The good news is that the answer to our “can common deworming drugs cure cancer” question might be just around the corner. Due to growing public interest, the National Cancer Institute recently announced it will investigate ivermectin specifically as a potential cancer treatment. I say it’s about time, since it’s highly likely that many potentially powerful cancer treatments have been swept under Big Pharma’s rug for decades. And now we wait. Let’s hope this research delivers the results millions of people with cancer so desperately need.

Kimberly Drake is a health journalist whose work appears in The Epoch Times, Healthline, Medical News Today, and GoodRx. She can be reached at [email protected].