Definition of Drug, antibiotic Drug, antibiotic: A drug used to
treat bacterial infections. The original definition of an
antibiotic was a substance produced by one microorganism that
selectively inhibits the growth of another microorganism.
However, wholly synthetic antibiotics (usually chemically
related to natural antibiotics) have since been produced that
accomplish comparable tasks. In 1926, Alexander Fleming
discovered penicillin, a substance produced by fungi that
appeared able to inhibit bacterial growth. In 1939, Edward Chain
and Howard Florey further studied penicillin and later carried
out trials of penicillin on humans (with what were deemed fatal
bacterial infections). Fleming, Florey and Chain shared the
Nobel Prize in 1945 for their work which ushered in the era of
antibiotics. Another antibiotic, for example, is tetracycline
(brand names: ACHROMYCIN and SUMYCIN), a broad-spectrum agent
effective against a wide variety of bacteria including
Hemophilus influenzae, Streptococcus pneumoniae, Mycop