Pharmacological action and antibacterial action-It has a broad antibacterial spectrum for Gram-positive bacteria and Gram-negative bacteria, especially for Staphylococcus and Streptococcus in Gram-positive bacteria. It has stronger antibacterial activity than the previous oral cephalosporins, and its mode of action is sterilization. -It is stable to β -lactamases produced by various bacteria, and also has good antibacterial activity to β -lactamase producing bacteria. The mechanism of action is to prevent the synthesis of bacterial cell walls. It has strong affinity for pbps (PBP) 1( 1a, 1bs), 2 and 3, but has different active sites for different bacteria. Toxicological study The acute and chronic toxicity of cefdinir in experimental animals such as rats and dogs showed that cefdinir was well tolerated. Cefdinib was not found to be teratogenic and mutagenic.