A PubMed search for “ivermectin” and “cancer” yields hundreds of preclinical studies, many conducted on cell cultures or mice. In the sector of alternative cancer treatments, few drugs have generated as much buzz—and controversy—as ivermectin. Once lauded for its ability to treat parasitic infections and awarded a Nobel Prize for its contribution to global health, ivermectin has more recently been at the center of misleading narratives, first as an alleged cure for COVID-19 and now as a so-called “cancer breakthrough.”Social media, podcasts, and even some patient communities are abuzz with stories of miraculous recoveries and scientific “breakthroughs.” But what’s driving this surge of interest, and does the science live up to the hype?For decades, ivermectin was best known as a safe and effective treatment for parasitic diseases like river blindness and scabies. Its impact was so significant that it earned its discoverers the Nobel Prize in 2015. But after being widely discredited as a COVID-19 treatment, ivermectin found new life in online cancer forums and alternative health circles, where it’s now promoted as a cheap, accessible alternative to mainstream cancer therapies.The renewed interest in ivermectin as a potential cancer therapy has largely been driven by non-scientific sources. On platforms like X (formerly Twitter), Substack, and YouTube, influential figures promote ivermectin as a natural, low-cost cure "suppressed by big pharma."One viral moment came during a widely viewed episode of The Joe Rogan Experience, in which actor Mel Gibson recounted how three friends with stage IV cancer reportedly became cancer-free after taking ivermectin and fenbendazole. That snippet, viewed by nearly 20 million people, has fueled speculation—despite the anecdotal nature of the claims.Further fanning the flames, public figures like Robert F. Kennedy Jr. have accused health authorities of deliberately suppressing ivermectin to favor profit-driven cancer treatments—a claim lacking credible evidence but resonating with those distrustful of traditional medicine.What Is Ivermectin Approved For?Ivermectin is a U.S. FDA-approved antiparasitic drug, used for treating river blindness (onchocerciasis), strongyloidiasis, lice, and scabies in humans. It’s also commonly used in veterinary medicine to treat parasitic infections in animals.Its development and application in tropical medicine were so impactful that the researchers behind ivermectin received the Nobel Prize in 2015. However, its uses have always remained confined to parasitic infections—not viral illnesses like COVID-19, and certainly not cancer.How Ivermectin Might Work Against Cancer?Ivermectin’s anticancer effects appear to be unrelated to its anti-parasitic action. Instead, the drug disrupts cancer cell signaling, impairs mitochondrial function, induces autophagy (a process that can kill cancer cells), and inhibits cancer stem cells. It also weakens the mechanisms that allow tumors to resist chemotherapy and evade the immune system.In the Brazilian rat study, nano-encapsulated ivermectin not only shrank tumors but also improved the health of surrounding brain tissue and reduced abnormal blood vessel growth—suggesting multiple avenues of attack against cancer.What the Science Says About Ivermectin and Cancer?A search of scientific literature reveals hundreds of studies linking ivermectin to cancer research. Some of these suggest that ivermectin may interfere with cancer cell metabolism, inhibit tumor growth, or boost immune response in lab-controlled environments. But—and this is critical—lab results do not equal human results.Dr. Peter P. Lee, chair of the Department of Immuno-Oncology at the Beckman Research Institute of City of Hope, has studied ivermectin's immune-stimulating effects in mice. While findings hinted at some tumor-modulating potential, they fell far short of demonstrating therapeutic value in humans.At the 2025 American Society of Clinical Oncology (ASCO) Annual Meeting, early results from a phase 1/2 trial combining ivermectin with immunotherapy in metastatic triple-negative breast cancer patients showed no significant benefit. Of the eight patients evaluated, six experienced disease progression, one had a partial response, and one achieved stable disease.Risks of Using Ivermectin as a Cancer TherapyPromoting ivermectin for cancer without evidence carries several dangers:Neurological toxicity: High doses can lead to seizures, confusion, blurred vision, or even coma.Drug interactions: Ivermectin can interfere with common cancer medications, such as blood thinners or immunotherapy agents.Treatment delays: Perhaps most concerning is the risk that patients may delay or forgo evidence-based cancer treatments in favor of unproven, alternative drugs. Such delays can allow the cancer to progress unchecked.False hope and financial exploitation: Some patients may spend time, money, and emotional energy pursuing unproven remedies, only to face worsening outcomes.Why the Sudden Surge in Popularity?Several factors have converged to make ivermectin a hot topic in cancer circles. Social media amplification has played a major role, with influencers and alternative health advocates promoting ivermectin as a cheap, “natural” alternative to mainstream cancer treatments. These promotions often rely on cherry-picked studies or anecdotal stories of success, rather than clinical evidence. Distrust in conventional oncology also fuels interest—many patients, disillusioned by the side effects, financial burden, or perceived limitations of standard therapies, are increasingly drawn to off-label or experimental alternatives like ivermectin. Preclinical breakthroughs, such as the much-publicized Brazilian nano-ivermectin study in animals, add to the intrigue by generating hopeful headlines, despite lacking human trial data. Finally, political and cultural overtones stemming from ivermectin’s controversial use during the COVID-19 pandemic have transformed the drug into a rallying point for individuals skeptical of established medical authorities, further complicating the public narrative around its potential role in cancer treatment.Where Does This Leave Patients and Doctors?While the science around ivermectin and cancer is evolving, the consensus among oncologists and researchers is clear: There is no solid evidence that ivermectin can cure or significantly treat cancer in humans. The most promising findings are still limited to laboratory and animal studies, and ongoing clinical trials have yet to show meaningful benefit in people.That said, the safety profile in small studies is reassuring, and the innovative use of nanotechnology to deliver ivermectin to brain tumors is a genuine scientific advance—one that warrants further research but not premature celebration.Curiosity Is Good—But Let's Stick to the ScienceThe buzz around ivermectin as a cancer cure is based more on anecdotes and viral claims than on real science. While early lab data may inspire future studies, there is currently no evidence that ivermectin can treat or cure cancer in humans. Ivermectin’s journey from Nobel-winning anti-parasitic to cancer “miracle drug” is a testament to both the power of scientific curiosity and the dangers of viral misinformation.Patients facing cancer deserve hope—but not false hope. Turning away from proven therapies in favor of unproven ones could have devastating consequences.