CEPHALOSPORINS

2. CEPHALOSPORINS(BETA LACTAM)

It was first isolated from  Cephalosporium acremonium fungus in 1945 , it showed excellent results on gram positive bacteria. More recent versions are showing broader activity against gram negative bacteria too.

Mechanism of action

• binding to specific penicillin-binding proteins.
• Inhibition of cell wall synthesis.
• Activation of autolytic (self-destructive) enzymes in the bacterial cell wall

Cephalosporins have been developed over several generations the most current is 5^th generation

1^st generation  – Cephalexin ,Cephradine, Cefadroxil, Cefazolin- they are used for skin, soft tissue and respiratory tract infections.

2^nd generation -Cefoxitin (cephamycin), Cefotetan (cephamycin), Cefuroxime, Cefprozil – treat sinusitis, otitis media, anaerobic infections like peritonitis,diverticulitis and for prophylaxis after colorectal surgery.

3^rd generation - have an improved structure able to treat a wide range of gram positive and negative infections to include; Lower respiratory tract infections,Skin and soft tissue infections,Uncomplicated gonorrhea,Urinary tract infections,Otitis media,Pelvic inflammatory disease,Surgical prophylaxis, Bacteria septicemia (blood infection),Meningitis,Bone infections,Joint infections,Intra-abdominal infections. The drugs include ceftriaxone, Cedax, Cefdinir, cefditoren, cefixime,Cefizox,Cefotaxime,cefpodoxime,ceftazidime,ceftibuten,ceftizoxime,ceftriaxone,Claforan, Fortaz, Rocephin.

4^th generation -Cefepime is the only available (FDA-approved) fourth-generation cephalosporin. Its active against Pseudomonas aeruginosa- a resistant bacteria responsible for nosocomial infections such as pneumonia. Other uses include; Moderate to severe pneumonia,Severe urinary tract infection, Skin and soft tissue infections, Complicated intra-abdominal infections

5^th generation -Ceftaroline (Teflaro), the only fifth- or advanced-generation cephalosporin approved by FDA in 2010 and its reserved for serious infections caused by multidrug-resistant infections like MRSA (methicillin-resistant S. aureus) and VRSA (vancomycin-resistant S. aureus)

Metabolism- liver

Elimination- renal

Pregnancy category - B

Adverse effects

-          GI disturbances

-          Haematologic changes-eg eosinophilia,leucopenia

-          Skin rshes-exanthema, uticaria,dermatitis

-          Headache, dizziness

-          Oliguria

3. CARBAPANEMS (BETA LACTAM)

complete blood count, para-cervical block, leukemia