Joseph Lister, Professor of surgery at Glasgow University, was the first to realize that the high post-operative mortality of his patients was due to the onset of blood poisoning (sepsis) caused by bacteria. Back then, the operating theatres were not the sterile places that they are today. In the early 19th century, they were awash with blood, tissue and amputated body parts. In 1865 Lister found that carbolic acid was an effective antiseptic. Dr Lister is likely more commonly known in connection with Listerine—the antiseptic mouthwash. While Dr Lister didn’t invent Listerine, it was named after him because the product is antiseptic and Dr Lister was the pioneer of antiseptic surgery.