Cephalosporins
First-generation cephalosporins are active predominantly against Gram-positive bacteria, such as Staphylococcus and Streptococcus. They are therefore used mostly for skin and soft tissue infections. Successive generations of cephalosporins have increased activity against Gram-negative bacteria. Mechanism of action - Cephalosporins disrupt the synthesis of the peptidoglycan layer forming the bacterial cell wall. The peptidoglycan layer is important for cell wall structural integrity. Side effects - Common adverse drug reactions associated are diarrhea, nausea, rash, electrolyte disturbances, and pain and inflammation at injection site. Resistance - Citrobacter freundii, Enterobacter cloacae, Neisseria gonorrhoeae, and Escherichia coli strains are resistant to cephalosporins.