Cefamandole is a second-generation cephalosporin with a high level of activity against common aerobic pathogens, both Gram-positive and Gram-negative. Eighty-five per cent of 20 recent clinical isolates of Bacteroides fragilis are sensitive and these data allied with its known activity against common aerobes reinforce its recommendation for the prophylaxis and treatment of severe hospital infections, particularly post-surgical cases with septicaemia.