Repurposing Ivermectin and Mebendazole for Cancer: What the New Real-World Data Tells Us, and What It Cannot
FUNCTIONAL MEDICINE INSIGHTS By Jill C. Carnahan, MD, ABIHM, ABoIM, IFMCP
Why This Conversation Matters Now
Drug repurposing, the practice of investigating well-known medications for new clinical uses, is one of the most exciting frontiers in modern oncology. Conventional cancer drug development is slow, expensive, and often ends in disappointment. Repurposing offers a different path. We start with molecules whose pharmacology, dosing, and safety profile are already well characterized in humans, then ask whether they might also disrupt the biology of cancer at clinically achievable concentrations.
Two old antiparasitic agents have moved to the center of this conversation: ivermectin, a macrocyclic lactone that earned the 2015 Nobel Prize for its impact on river blindness, and mebendazole, a benzimidazole used safely for decades against intestinal helminths and cerebral echinococcosis. Both drugs are inexpensive, widely available, and remarkably well tolerated. Both also show a striking range of anticancer activity in laboratory and animal models. The question that thoughtful physicians and patients keep asking is whether any of this preclinical promise translates to meaningful benefit in human beings with cancer.
