Cephalosporins are a group of broad spectrum, semi-synthetic beta-lactam antibiotics derived from the mould Cephalosporium. They are divided into three groups: Cephalosporin N and C are chemically related to penicillins and Cephalosporin P a steroid antibiotic resembles fusidic acid.
The mechanism of action of cephalosporins is the same as penicillins. They interfere with bacterial cell wall synthesis.
Semisynthetic broad-spectrum cephalosporins have been produced by the addition of different side chains, to the Cephalosporin C nucleus.
They are classified according to the chronological order in which they were produced.