Where does Penicillin Come from?

Penicillin can be found in your local pharmacy and if you have a prescription from your doctor you will be able to get it. Oops I believe you meant where does penicillin come from? Penicillin actually comes from a mold called Penicillium genus and was discovered in 1928 purely by accident by Dr. Alexander Fleming. Dr. Flemming had accidentally cross contaminated a petri dish with staphylococci with a mold called Penicillium genus which had killed the staphylococci that had come in contact with it.