Cefazolin / Cephazolin

ADMINISTRATION ROUTES:

IV

ALTERNATIVE NAMES:

Cefazolin, cephazolin

ICU INDICATIONS:

1. Prophylaxis around surgery

2. Treatment of infections caused by susceptible organisms

PRESENTATION AND ADMINISTRATION:

IV:

1 gm vials of powder

Reconstitute with 2.5 mL of water for injection ONLY to make a total of 3 mL of final solution with a concentration of 330 mg/mL then shake well until all powder is dissolved. Store at room temperature

Compatible with:

Normal saline, glucose and sodium chloride, 5% dextrose, 10% dextrose, Hartmanns

Administer reconstituted solution by direct injection over 3-5 minutes

DOSAGE:

IV:

1-2 gm IV q6-8hrly

Note: for prophylaxis after cardiac surgery, patients should be given 1 gm 3 hours after ICU admission and 1 gm 8 hours later

DOSAGE IN RENAL FAILURE AND RENAL REPLACEMENT THERAPY:

Dose in renal impairment

Dose in renal replacement therapy

DOSAGE IN PAEDIATRICS:

25-50 mg/kg IV q6-8hrly

CLINICAL PHARMACOLOGY:

Cefazolin for injection is a 1st generation cephalosporin for parenteral administration. It has bactericidal action resulting from inhibition of cell wall synthesis. When organisms are susceptible, Cefazolin sodium is active against the following organisms in vitro and in clinical infections:

• Staphylococcus aureus (including penicillinase-producing strains)
• Staphylococcus epidermidis
• Group A beta-haemolytic streptococci and other strains of streptococci (many strains of enterococci are resistant)
• Streptococcus pneumoniae
• Escherichia coli
• Proteus mirabilis
• Klebsiella species
• Enterobacter aerogenes
• Haemophilus influenzae

Most strains of indole positive Proteus (Proteus vulgaris), Enterobacter cloacae, Morganella morganii and Providencia rettgeri are resistant. Serratia, Pseudomonas, Mima, Herellea species are almost uniformLy resistant to cefazolin.

CONTRAINDICATIONS:

1. Hypersensivity to cephalosporins

WARNINGS:

Anaphylaxis

Cephalosporins are a common cause of anaphylactic reactions and cross reactivity with penicillins may occur

Pseudomembranous colitis

Pseudomembranous colitis has been reported with nearly all antibacterial agents, including cefazolin, and may range in severity from mild to life-threatening. Therefore, it is important to consider this diagnosis in patients who present with diarrhoea subsequent to the administration of antibacterial agents

PRECAUTIONS:

General:

Prescribing cefazolin in the absence of a proven or strongly suspected bacterial infection or a prophylactic indication is unlikely to provide benefit to the patient and increases the risk of the development of drug-resistant bacteria.

Positive direct Coombs' tests have been reported during treatment with the cephalosporin antibiotics. It should be recognised that a positive Coombs' test may be due to the drug.

Laboratory Tests:

No tests additional to usual ICU tests are required

Drug/Laboratory Test Interactions :

A false positive reaction for glucose in the urine may occur with Benedict's solution, Fehling's solution or with Clinitest tablets, but not with enzyme-based tests such as Clinistix.

Positive direct and indirect antiglobulin (Coombs) tests have occurred; these may also occur in neonates whose mothers received cephalosporins before delivery.

IMPORTANT DRUG INTERACTIONS IN ICU:

None of note.

ADVERSE REACTIONS:

Body as a whole:

Anaphylaxis, itching, drug fever, Stevens-Johnson syndrome

Haemopoietic System:

Neutropaenia, leukopaenia, thrombocytopaenia, thrombocythaemia, eosinophilia

Skin:

Skin rash

Gastrointestinal System:

Diarrhoea, oral candidiasis (oral thrush), vomiting, nausea, stomach cramps, anorexia and pseudomembranous colitis. Transient rises in ALT, AST, and alkaline phosphatase levels has been observed. As with other cephalosporins, reports of hepatitis have been received.

Cephalosporin-Class Adverse Reactions:

In addition to the adverse reactions listed above that have been observed in patients treated with cefaclor, the following reactions and altered laboratory tests have been reported for cephalosporin-class antibiotics: fever, abdominal pain, superinfection, renal dysfunction, toxic nephropathy, haemorrhage, false positive test for urinary glucose, elevated bilirubin, elevated LDH, and pancytopaenia.

Several cephalosporins have been implicated in triggering seizures, particularly in patients with renal impairment when the dosage was not reduced. If seizures associated with drug therapy occur, the drug should be discontinued. Anticonvulsant therapy can be given if clinically indicated