Penicillin is a common antibiotic, used to treat bacterial infections. It was one of the first to be discovered, and worked well against staphylococci and streptococci. Many strains of bacteria are now resistant. Chemists keep changing part of its structure in the effort to keep it working against the bacteria.
Penicillin was discovered by Scottish scientist Sir Alexander Fleming in 1928, but it was not mass-produced until 1940. The antibiotic is naturally produced by fungi of the genus Penicillium. There is now a whole group of antibiotics derived from Penicillium including penicillin G, procaine penicillin, benzathine penicillin, and penicillin V.
Penicillin was discovered when Fleming noticed a mold that was stopping bacteria from growing in a petri dish. Australian scientist Howard Walter Florey made the penicillin mold into a medicine. Together with another scientist Ernst Boris Chain, Fleming and Florey were given the Nobel Prize for Medicine in 1945.
Some people are allergic to penicillin. Symptoms include nausea, diarrhea, or rash. Rarely, patients who are allergic to penicillin get a fever, vomit, or have serious skin irritation. Because it is such a popular antibiotic, penicillin is the most common cause of serious allergic reactions to a drug. They are now used regularly in hospitals.
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