<P> The challenge of mass - producing this drug was daunting . On March 14 , 1942 , the first patient was treated for streptococcal septicemia with US - made penicillin produced by Merck & Co . Half of the total supply produced at the time was used on that one patient . By June 1942 , just enough US penicillin was available to treat ten patients . In July 1943 , the War Production Board drew up a plan for the mass distribution of penicillin stocks to Allied troops fighting in Europe . The results of fermentation research on corn steep liquor at the Northern Regional Research Laboratory at Peoria , Illinois , allowed the United States to produce 2.3 million doses in time for the invasion of Normandy in the spring of 1944 . After a worldwide search in 1943 , a mouldy cantaloupe in a Peoria , Illinois market was found to contain the best strain of mould for production using the corn steep liquor process . Pfizer scientist Jasper H. Kane suggested using a deep - tank fermentation method for producing large quantities of pharmaceutical - grade penicillin . Large - scale production resulted from the development of a deep - tank fermentation plant by chemical engineer Margaret Hutchinson Rousseau . As a direct result of the war and the War Production Board , by June 1945 , over 646 billion units per year were being produced . </P>
when was penicillin first introduced to the public
1942