A new study shows that a toxin from the microbe that causes anthrax can silence multiple types of pain in mice. Researchers found the toxin targets pain-sensing cells to alter signaling and block pain. Building on that finding, researchers engineered an anthrax protein vehicle to deliver different types of treatments into pain receptors and modulate nerve-cell function. The findings can inform the design of therapies that selectively target pain-sensing fibers without the widespread systemic effects of opioids and other pain killers.