Penicillin: The Accidental Discovery That Changed Modern Medicine

Penicillin is often credited as the world’s first true antibiotic, and its discovery marked a turning point in medical history. Found by accident in 1928 by Scottish bacteriologist Alexander Fleming, penicillin has saved countless lives and transformed how bacterial infections are treated.

The Discovery

While working at St. Mary’s Hospital in London, Alexander Fleming returned from vacation to find a Petri dish of Staphylococcus bacteria contaminated by a blue-green mold. Around the mold, he noticed a clear area where bacteria had been killed. The mold was identified as Penicillium notatum, and the substance it