Cefazolin : Therapeutic uses, Dosage & Side Effects
Cefazolin (Cefazoline or Cephazolin) is an prototype first generation cephalosporin. It is used for treating bacterial infections or preventing bacterial infections before, during, or after certain surgeries. Specifically it is used to treat cellulitis, urinary tract infections, pneumonia, endocarditis, joint infection, and biliary tract infections.
Dose : 0.25 g 8 hourly (mild cases), 1 g 6 hourly (severe cases) i.m. or i.v.
Route : IM, IV
Onset of action : ?
Plasma Half-life : 2 hour
Duration of action : ?
Bioavailability : ?
Plasma protein binding : ?
Metabolism : ?
Pregnancy risk category : B
Chemical formula : C14H14N8O4S3
IUPAC name : (6R,7R)-3-{[(5-methyl-1,3,4-thiadiazol-2-yl)thio]methyl}-8-oxo-7-[(1H-tetrazol-1-ylacetyl)amino]-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid
Trade name : Kefzol, Alcizon, Orizolin, Ancef, Cefacidal, Cefamezin, Cefrina, Elzogram, Faxilen, Gramaxin, Kefol, Kefzolan, Kezolin, Novaporin, Reflin, Zinol, Zolicef
Antibacterial spectrum : The first-generation cephalosporins are resistant to the staphylococcal penicillinase (that is, they cover MSSA) and also have activity against Proteus mirabilis, E. coli, and K. pneumoniae.
Cefazolin is active against most PnG sensitive organisms, i.e. Streptococci (pyogenes as well as viridans), gonococci, meningococci, C. diphtheriae, H. influenzae, clostridia and Actinomyces. Activity against Klebsiella and E. coli is relatively high, but it is quite susceptible to staphylococcal beta lactamase.
Therapeutic uses : Cefazolin is the preferred parenteral first generation cephalosporin, especially for surgical prophylaxis. It has following uses :
- Used as alternatives to PnG; particularly in allergic patients (but not who had anaphylactic reaction).
- Used to treat Penicillinase producing staphylococcal infections.
- Used to treat Respiratory tract infections due to Streptococcus pneumoniae, Klebsiella species, H. influenzae, Staph. aureus (penicillin-sensitive and penicillin-resistant), and group A beta-hemolytic streptococci.
- Used to treat Urinary tract infections due to E. coli, and Proteus mirabilis, Klebsiella species, and some strains of enterobacter and enterococci.
- Used to treat Biliary infections due to E. coli, various strains of streptococci, P. mirabilis, Klebsiella species, and S. aureus.
- Used to treat Skin and skin structure infections due to S. aureus (penicillin-sensitive and penicillin-resistant), group A beta-hemolytic streptococci, and other strains of streptococci.
- Used to treat Bone and joint infections due to S. aureus.
- Used to treat Septicemia (sepsis) due to S. pneumoniae, S. aureus, (penicillin-sensitive and penicillin-resistant), P. mirabilis, E. coli, and Klebsiella species.
- Used to treat Genital infections due to E. coli, and P. mirabilis, Klebsiella species, and some strains of enterococci.
- Used to treat Endocarditis due to S. aureus (penicillin-sensitive and penicillin-resistant) and group A beta-hemolytic streptococci.
There is no penetration into the central nervous system and therefore cefazolin is not effective in treating meningitis.
Mechanism of action : Cephalosporins cause inhibition of bacterial cell wall synthesis. i.e. they have the same mechanism of action as penicillin. However, they bind to different proteins than those which bind penicillins.
Side effects : Cephalosporins are generally well tolerated, but are more toxic than penicillin. Cefazolin may exhibit following side effects :
- Hypersensitivity reactions caused by cephalosporins are similar to penicillin, but incidence is lower. Rashes are the most frequent manifestation, but anaphylaxis, angioedema, asthma and urticaria have also occurred.
- Diarrhoea, stomach pain or upset stomach, vomiting,
- Clostridium difficile-associated diarrhea.
Drug Interactions : Cefadroxil may interact with following drugs :
- Probenecid : Increased and more prolonged cephalosporin blood levels.
Contraindications :
- Contraindicated in patients who have a history of immediate hypersensitivity reactions to cefazolin or the cephalosporin class of antibacterial drugs, penicillins, or other beta-lactams.
For detailed query or in case of uncertainty, Always consult your doctor or pharmacist.
