Cephalosporins are a class of beta-lactam antibiotics originally derived from the fungus Cephalosporium acremonium. They work by inhibiting cell wall synthesis in bacteria, preventing the formation of peptidoglycan and leading to cell death. Cephalosporins are administered orally or parenterally and are widely distributed throughout the body, with most being excreted unchanged through the kidneys. Potential adverse effects include hypersensitivity reactions, gastrointestinal issues, pain at injection sites, nephrotoxicity when combined with other drugs, and bleeding due to effects on coagulation factors or platelets.

1. Cephalosporins

2. Introduction
• Cephalosporins are Beta-lactam antibiotics.
• Source : Cephalosporium acremonium, a fungus
• Later synthetic cephalosporins were developed.
• They are divided into four generations based on their general features and
antibacterial activity.

3. Mechanism of action
Cephalosporins
Inhibits transpaptidase
Preventsts peptidoglycan synthesis
Cell wall deficient forms(Spheroplasts and filamentous forms)
Autolysis
Cell death

4. Pharmacokinetics
Administration: Oral or parenteral
distribution: Throughout the body
Metabolism: Some drugs are metabolized in liver via deacetylation but most of the drugs
remain unchanged.
Excretion: Excreted unchanged through kidney either by glomerular filtration or by tubular
secretion. Deacetylated Cefotaxime is excreted through bile.

5. Source: Pharmacology of dentistry

6. Adverse effects
Hypersensitivity: They are skin rashes, urticaria and rarely anaphylaxis.
Gastrointestinal disturbances: Diarrhoea, vomiting and anorexia.
Pain at the site of i.m. injection mainly with cephalothin.
Intravenous cephalosporins can cause thrombophlebitis.
Nephrotoxicity may occur. Co-administration of cephalothin and gentamicin increases the
nephrotoxicity.
Intolerance to alcohol (a disulfi ram-like reaction) has been reported with cefotetan and cefoperazone.
Severe bleeding can occur either due to hypoprothrombinaemia (which responds to vitamin K therapy)
or thrombocytopaenia and/or platelet dysfunction.