Antimicrobial activity, pharmacokinetics, therapeutic indications and adverse reactions of ceftazidime

Ceftazidime is an aminothiazolyl cephalosporin with potent activity against gram-negative bacteria including multiresistant strains of Pseudomonas aeruginosa. It has limited activity against gram-negative anaerobes, is less active against some gram-positive cocci than other newer beta-lactam compounds and is inactive against Streptococcus faecalis and methicillin-resistant Staphylococcus aureus. Ceftazidime is stable against common plasmid and chromosomally mediated beta-lactamase produced by Enterobacteriaceae and Pseudomonas sp. Its pharmacokinetic properties are similar to those of moxalactam and ceftizoxime, and it has a half-life of 1.9 hours. Excretion is by glomerular filtration. It is not metabolized. Ceftazidime penetrates into most body tissue and fluids, including cerebrospinal fluid, and produces therapeutic levels against most of the pathogenic gram-negative bacteria, including P. aeruginosa. Ceftazidime accumulates during renal failure, but is removed by hemodialysis and peritoneal dialysis. As a single agent it has been shown effectively to treat meningitis; urinary tract infections; gram-negative pneumonia; bone, joint and skin infections; and obstetric and gynecologic infections due to susceptible organisms. When combined with an agent that is effective against gram-positive organisms, it is also beneficial in the treatment of infections in seriously ill neonates. Different investigators have used ceftazidime alone or in combination with other agents in the successful treatment of infections in immunosuppressed patients. Adverse reactions have been few and are mostly reversible laboratory findings. The effects of ceftazidime on prothrombin synthesis and platelet function have been minimal, and no drug-induced clinical bleeding has been reported.