CEPHALORIDINE IS A BETA-LACTAM ANTIBIOTIC AND HAS A BACTERICIDAL ACTION AGAINST GRAM-POSITIVE AND GRAM-NEGATIVE BACTERIA. IT EXERTS ITS KILLING ACTION ON GROWING AND DIVIDING BACTERIA BY INHIBITING BACTERIAL CELL-WALL SYNTHESIS, ALTHOUGH THE MECHANISMS INVOLVED ARE STILL NOT PRECISELY UNDERSTOOD. IT HAS PROPERTIES SIMILAR TO
THOSE OF CEPHALOTHIN , BUT IS MORE NEPHROTOXIC AND IS SELDOM USED NOW.