Cefazolin is a semi-synthetic cephalosporin antibiotic intended for parenteral use. As all beta-lactam antibiotics, cefazolin has a bactericidal action which is based on the violation of the synthesis of bacterial cell membranes.
Cefazolin is the gold standard, the least toxic 1st generation cephalosporin antibiotic for parenteral administration.
The spectrum of antibacterial action of Cefazolin covers the following pathogens: Staphylococcus aureus (including penicillinase producing strains), Staphylococcus epidermidis (Staphylococcus with resistance to methicillin, are resistant to cefazolin), beta-hemolytic group A streptococci and other strains of streptococci (many strains of enterococci are resistant to the drug); Streptococcus (Diplococcus) pneumoniae, E. coli, Proteus mirabilis, Klebsiella sp., Enterobacter aerogenes, Haemophilus influenzae. Most strains of indole-positive Proteus (Proteus vulgaris), as well as Enterobacter cloacae, Morganella morganii, Providencia rettgeri, Serratia, Pseudomonas and Acinetobacter are resistant to Cefazolin.
Cefazolin is poorly absorbed from the gastrointestinal tract and therefore is used intramuscularly or intravenously. For intramuscular injections, the drug should be diluted in a 0.5% solution of lidocaine.
Due to its pharmacokinetic characteristics, the drug is indicated for a variety of infections caused by susceptible to Cefazolin pathogens. The spectrum of indications for Cefazolin include:
- respiratory tract infections such as bronchitis and pneumonia
- infections of the genitourinary system, such as pyelonephritis, cystitis, urethritis and prostatitis
- infections of the skin and soft tissues
- infections of the biliary tract
- bone and joint infections
- systemic septic infections
- prevention of infections during surgery (hysterectomy, cholecystectomy, open heart surgery, operations on bones and joints)
The drug is contraindicated in patients allergic to Cefazolin or to other cephalosporin antibiotics.
Possible side effects
Cefazolin may cause allergic reactions. There have been cases of drug fever, skin rash, pruritus, eosinophilia, allergic nephritis and anaphylactic reactions. In some cases, there were observed neutropenia, leukopenia, thrombocythemia, and the positive results of direct and indirect Coombs test. There have been sporadic cases of hypoprothrombinemia, which was of transient nature with the use of vitamin K.
During therapy with Cefazolin may appear a transient increase in levels of urea nitrogen level in the blood. In rare cases there may be a temporary increase in the levels of alkaline phosphatase, AST and ALT.
Unwanted side effects from the gastrointestinal tract during the treatment with Cefazolin may include loss of appetite, diarrhea, nausea and vomiting. As rare side effects were observed candidiasis and pseudomembranous colitis.
Intramuscular injections of Cefazolin can be painful and cause infiltration of the tissue at the site of injection. In some patients, after intravenous administration of Cefazolin, was found phlebitis.
Cefazolin overdose or accumulation in patients with renal insufficiency can cause neurotoxic effects. With this, there is increased convulsive readiness, tonic–clonic seizures, vomiting and tachycardia. Elimination of drug from the body is achieved by hemodialysis.
Special precautions for safe use
In patients with impaired renal function it is required to select the right dosage level and intervals between the Cefazolin injections depending on the severity of renal dysfunction. In the case of unstable kidney function, a constantly monitoring of the levels of Cefazolin in the serum will ensure safety of the drug use. If there are signs of allergic reactions, the drug should be discontinued and, if necessary, to assign an appropriate symptomatic treatment for the patient. It should be kept in mind the possibility of cross-allergy with other cephalosporin antibiotics, and, in some cases, with penicillin antibiotics.
In the case of patients with toxic reactions, as well as signs of an overdose of Cefazolin, the excretion of the drug from the body can be accelerated by hemodialysis. Peritoneal dialysis in this case would be ineffective.