After testing it on some patients, they discovered that it was effective. Pharmaceutical companies in the U.S. and Britain began to produce large quantities of penicillin. At first, it was used only for war casualties, then in 1944, it was made available to civilians. By 1945, penicillin was being used by medical professionals all over the world. It is used to treat scarlet fever, syphilis, diphtheria, bronchitis, meningitis, blood poisoning, pneumonia, and many other ailments.
Some people are allergic to penicillin, however, it has a wide margin of safety.
Injections of up to 100 million units have been given without any ill effects. Much of the penicillin manufactured is semisynthetic, but all originate from the mold penicillium notatum. In 1944, Fleming was knighted for his contribution to the field of medicine. He was thereafter known as Sir Alexander Fleming. In 1945, Fleming, along with Florey and Chain, was awarded a Nobel Prize for his discovery of penicillin.