Vacor was a rodenticide that was marketed for a brief time between 1975-1979. It was originally thought to be safe for humans, but was pulled off the market in 1979 by the manufacturer. It is now banned. This poison works in a unique way—it destroys the pancreas cells that are responsible for producing insulin. It essentially causes a permanent, chemically-induced diabetes which happens hours to days after the ingestion. Patients who survived serious vacor poisoning required insulin injections for the rest of their lives.