Key Takeaways
- Ivermectin is an FDA-approved antiparasitic drug. It is not approved or proven to treat cancer.
- Laboratory and animal studies have shown some anticancer activity, but lab results are not the same as human results.
- As of 2026, there are no completed human clinical trials showing that ivermectin treats colorectal cancer, or any cancer.
- Self-treating with ivermectin, especially veterinary products or high doses, can cause serious harm and may delay proven treatment.
- Talk to your oncologist and ask about clinical trials before considering any unproven treatment.
Why are people talking about ivermectin for cancer?
Recently, former New York Rangers player Ron Duguay shared publicly that following his stage IV colon cancer diagnosis, he has turned to ivermectin as part of his treatment approach. His story gained widespread attention after a high-profile episode of The Joe Rogan Experience featuring Mel Gibson, on which claims were made about repurposed drugs, including ivermectin, as potential cancer treatments.
We understand why stories like this are compelling. When someone you admire faces the same diagnosis as you or your loved one, and when conventional treatment feels uncertain, hope can feel like the most powerful medicine. Our goal here is not to dismiss that hope, but to help our community understand what the science does, and doesn’t, actually support.
What is ivermectin?
Ivermectin is an antiparasitic medication with a genuinely impressive track record. Its development earned researchers Satoshi Ōmura and William Campbell a share of the 2015 Nobel Prize in Physiology or Medicine (NobelPrize.org, 2015). It is FDA-approved and widely used to treat parasitic infections such as river blindness and strongyloidiasis, and it is considered safe and effective for those approved uses (U.S. Food and Drug Administration).
During the COVID-19 pandemic, ivermectin surged in popularity amid claims, ultimately unsupported by rigorous clinical evidence, that it could fight the coronavirus. A Cochrane systematic review, the gold standard of evidence-based medicine, concluded that for outpatients, there is currently low- to high-certainty evidence that ivermectin has no beneficial effect for people with COVID-19 (Popp et al., Cochrane Database of Systematic Reviews, 2022; DOI: 10.1002/14651858.CD015017.pub3). This history of premature claims is important context as ivermectin now enters a new wave of speculation, this time around cancer.
What does the research say about ivermectin and colorectal cancer?
To be clear: there is published laboratory research exploring ivermectin’s potential anticancer properties. This research is real, and it is worth understanding, but it needs to be understood correctly.
Based on articles retrieved from PubMed, several preclinical (lab-based) studies have investigated ivermectin and colorectal cancer:
- Cell line studies have shown that ivermectin can inhibit colorectal cancer cells grown in a dish. One 2021 study in Frontiers in Pharmacology found that ivermectin suppressed cell proliferation by promoting a reactive-oxygen-species-mediated mitochondrial apoptosis pathway and inducing cell cycle arrest in colorectal cancer cells, suggesting ivermectin might be a new potential anticancer drug for human colorectal cancer. (DOI: 10.3389/fphar.2021.717529)
- Drug resistance research conducted in mice found that ivermectin at very low doses, which did not induce obvious cytotoxicity, drastically reversed the resistance of tumor cells to chemotherapeutic drugs both in vitro and in vivo. The mechanism involved suppression of a protein called P-glycoprotein via the EGFR signaling pathway. (DOI: 10.1186/s13046-019-1251-7)
- A 2025 study in Anticancer Research examined ivermectin combined with another experimental agent against colon cancer cells versus normal cells, finding selective synergistic anti-cancer efficacy against colon cancer cells, indicating clinical potential for metastatic colorectal cancer. (DOI: 10.21873/anticanres.17600)
- Animal studies in rats have also shown some protective signals against chemically induced colon cancer. (DOI: 10.1016/j.jsps.2022.06.024)
Can ivermectin cure colorectal cancer in humans?
The honest answer, based on the evidence available today, is no. This is the critical question, and it gets to the heart of how medical science works.
Lab results are not the same as human treatment. Every cancer drug that has ever succeeded in clinical trials first looked promising in a lab dish or a mouse model. But the vast majority of compounds that are exciting in preclinical research fail when tested in humans, because the human body is incomparably more complex, because safe concentrations in cells may be toxic at the doses needed in a person, and because cancer biology behaves differently in a living patient than in isolated cells.
The concentrations of ivermectin used in many of these lab studies are significantly higher than what is safely achievable in human blood at standard doses. This is a fundamental hurdle that has not yet been addressed in published clinical data.
There are no completed clinical trials in humans. As of today, there is no published randomized controlled trial demonstrating that ivermectin improves outcomes (survival, tumor shrinkage, or quality of life) in any cancer patient. The preclinical findings are genuinely interesting to researchers and have motivated further investigation, but they have not yet cleared the bar of human evidence.
What about fenbendazole for cancer?
The Joe Rogan/Mel Gibson podcast episode also featured discussion of fenbendazole, an antiparasitic drug used in veterinary medicine. It is important for our community to know that fenbendazole is not approved for human use at all. While some anecdotal reports and early laboratory research exist, there are no clinical trials supporting its use in humans, and its safety profile in human patients has not been established.
Is it safe to take ivermectin for cancer?
Choosing to take ivermectin outside of medical supervision for cancer carries real risks:
Delaying proven treatment. For colorectal cancer, especially stage IV, timing of evidence-based treatment matters enormously. Delaying surgery, chemotherapy, targeted therapy, or immunotherapy in favor of unproven alternatives can allow cancer to progress.
Drug interactions. Ivermectin can interact with other medications, including some used in cancer treatment.
False reassurance. Believing an unproven treatment is working can lead patients to forgo monitoring and checkups that catch progression early.
Dosing and safety. The doses explored in some lab studies are far above what is available or safe in standard human formulations. To reach those levels, some people turn to veterinary products or take very high doses, which can cause serious harm. Ivermectin overdose has been linked to nausea and vomiting, dangerously low blood pressure, liver injury, and neurological effects such as confusion, balance problems, seizures, and, in severe cases, coma (U.S. Food and Drug Administration; CDC Health Alert Network, 2021).
What should I do if I’m considering ivermectin?
The Fight Colorectal Cancer community stands for hope grounded in evidence. Here is how we encourage you to navigate this:
Talk to your oncologist. If you are curious about ivermectin or other repurposed drugs, bring it up openly with your care team. They can help you understand the current evidence and whether any clinical trials might be appropriate for you.
Look for clinical trials. The right way to access experimental treatments is through properly designed clinical trials, where safety is monitored and results can benefit future patients. Visit clinicaltrials.gov to search for trials enrolling colorectal cancer patients.
Be cautious about podcast medicine. Celebrity testimonials and anecdotal reports, however heartfelt, are not a substitute for clinical evidence. They reflect individual experience, not population-level safety and efficacy.
Stay engaged with the research. The preclinical science around drug repurposing, including ivermectin, is legitimately interesting. It may yield something meaningful in the future. Follow peer-reviewed developments through organizations like Fight Colorectal Cancer, the American Society of Clinical Oncology (ASCO), and the National Cancer Institute (NCI).
The Bottom Line
Ivermectin is a proven, Nobel Prize-winning antiparasitic drug. Laboratory and animal studies have raised genuinely interesting questions about whether it might one day play a role in cancer treatment. But as of today, there is no clinical trial evidence that it can treat colorectal cancer, or any cancer, in humans.
We share Ron Duguay’s diagnosis with thousands of people in our community, and we hold space for the very human desire to try anything that offers hope. But the best hope we can offer is this: trust the science, ask your oncologist, and know that researchers around the world are actively pursuing the next breakthroughs in colorectal cancer treatment every day.
Frequently Asked Questions
Can ivermectin cure colorectal cancer?
No. There is no clinical trial evidence that ivermectin can treat colorectal cancer, or any cancer, in humans. The supportive research that exists is preclinical, meaning it was done in cell cultures and animals, not people.
Is ivermectin safe to take for cancer?
At the FDA-approved doses used for parasitic infections, ivermectin is considered safe. The much higher doses discussed for cancer are not proven safe, and overdose can cause dangerously low blood pressure, liver injury, seizures, and coma (U.S. FDA; CDC Health Alert Network, 2021).
What did Joe Rogan and Mel Gibson say about ivermectin and cancer?
On a widely shared episode of The Joe Rogan Experience, Mel Gibson discussed claims that repurposed drugs such as ivermectin and fenbendazole could help treat cancer. These claims are not supported by clinical evidence in humans.
Does fenbendazole treat cancer?
Fenbendazole is an antiparasitic used in veterinary medicine and is not approved for human use. There are no human clinical trials showing that it treats cancer.
Are there clinical trials of ivermectin for cancer?
Laboratory research is ongoing, but as of 2026 there are no completed human clinical trials showing that ivermectin benefits cancer patients. You can search ClinicalTrials.gov for trials enrolling colorectal cancer patients.
Should I stop my cancer treatment to try ivermectin?
No. Delaying proven treatments such as surgery, chemotherapy, targeted therapy, or immunotherapy can allow cancer to progress. Talk with your oncologist before making any changes to your care.
References
Cell line study (colorectal cancer). Frontiers in Pharmacology, 2021. DOI: 10.3389/fphar.2021.717529 https://doi.org/10.3389/fphar.2021.717529
Drug-resistance study (in mice). Journal of Experimental & Clinical Cancer Research, 2019. DOI: 10.1186/s13046-019-1251-7 https://doi.org/10.1186/s13046-019-1251-7
Combination study (colon cancer cells). Anticancer Research, 2025. DOI: 10.21873/anticanres.17600 https://doi.org/10.21873/anticanres.17600
Chemically induced colon cancer (in rats). Saudi Pharmaceutical Journal, 2022. DOI: 10.1016/j.jsps.2022.06.024 https://doi.org/10.1016/j.jsps.2022.06.024
Popp M, et al. Ivermectin for preventing and treating COVID-19. Cochrane Database of Systematic Reviews, 2022. DOI: 10.1002/14651858.CD015017.pub3 https://doi.org/10.1002/14651858.CD015017.pub3
U.S. Food and Drug Administration. Why You Should Not Use Ivermectin to Treat or Prevent COVID-19. https://www.fda.gov/consumers/consumer-updates/ivermectin-and-covid-19
CDC Health Alert Network. Rapid Increase in Ivermectin Prescriptions and Reports of Severe Illness, 2021. https://archive.cdc.gov/emergency_cdc_gov/han/2021/han00449.asp
The Nobel Prize in Physiology or Medicine 2015. NobelPrize.org. https://www.nobelprize.org/prizes/medicine/2015/summary/
Find a clinical trial. ClinicalTrials.gov. https://clinicaltrials.gov
This article is for educational purposes and is not medical advice. For questions about your treatment plan, always consult your oncologist or a board-certified gastroenterologist.