Fazef Mechanism of Action

Pharmacology: Pharmacodynamics/Pharmacokinetics: After intramuscularly administration of Cefazolin (Fazef) to normal volunteers, the mean serum concentration were 37 mcg/mL at 1 hour and 3 mcg/mL at 8 hours following a 500 mg dose, and 64 mcg/mL at 1 hour and 7 mcg/mL at 8 hours following a 1 gram dose.
Studies have shown that the following intravenous administration of Cefazolin for injection to normal volunteers, mean serum concentrations peaked at approximately 4 mcg/mL at 8 hours for a 1 gram dose.
The serum half-life of Cefazolin (Fazef) is approximately 1.8 hours following I.V. administration and approximately 2.0 hours following I.M administration.
In a study (using normal volunteers) of constant intravenous infusion with dosage of 3.5 mg/kg for 1 hour (approximately 250 mg) and 1.5 mg/kg the next 2 hours (approximately 100 mg), Cefazolin (Fazef) produced a steady serum level at the third hour of approximately 28 mcg/mL.
Studies in patients hospitalized with infections indicate that Cefazolin (Fazef) produces a mean peak serum level approximately equivalent to those seen in normal volunteers.
Bile levels in patients without obstructive biliary disease can reach or exceed serum levels by up to five times; however, in patients with obstructive biliary disease, bile levels of Cefazolin (Fazef) are considerably lower than serum level (<1.0 mcg/mL).
In synovial fluid, the Cefazolin (Fazef) level becomes comparable to that reached in serum at about 4 hours after drug administration.
Studies of cord blood show prompt transfer of Cefazolin (Fazef) across the placenta. Cefazolin (Fazef) is present in very low concentrations in the milk of nursing mothers. 
Cefazolin (Fazef) is excreted unchanged in the urine. In the first 6 hours approximately 60% of the drug is excreted in the urine and this increased to 70% to 80% within 24 hours. Cefazolin for injection achieves peak urine concentration of approximately 2400 mcg/mL and 4000 mcg/mL respectively following 500 mg and 1g intramuscular doses.
In patients undergoing peritoneal dialysis (2L/hr), Cefazolin (Fazef) produced mean serum levels of approximately 10 and 30 mcg/mL after 24 hours instillation of a dialyzing solution containing 50 mg/L and 150 mg/L respectively. Mean peak levels were 29 mcg/mL (range 13-144 mcg/mL) with 50 mg/L (three patients), and 72 mcg/mL (range 26-142 mcg/mL) with 150 mg/L (six patients). 
Intraperitoneal administration of Cefazolin (Fazef) is usually well tolerated.
Controlled studies on adult normal volunteers, receiving 1 gram 4 times a day for 10 days, monitoring CBC, SGOT, SGPT, bilirubin, alkaline phosphatase, BUN, creatinine, and urinalysis, indicated no clinically significant changes attributed to Cefazolin (Fazef).