Ceftazidime

Ceftazidimum

For medical students2 min readUpdated 2026-10-10

Ceftazidime is a parenteral third-generation cephalosporin with an expanded spectrum of antimicrobial activity. The drug is one of the most effective agents for treating infections caused by Pseudomonas aeruginosa.

Pharmacological classBeta-lactam antibiotic, third-generation cephalosporin.

Spectrum of activityGram-negative bacteria, including *Pseudomonas aeruginosa*.

FormulationPowder for solution for injection in 0.5 g and 1.0 g vials.

Route of administrationIntramuscular and intravenous (bolus).

Mechanism of Action

Ceftazidime belongs to beta-lactam antibiotics. Its action is based on the inhibition of bacterial cell wall synthesis. The drug is highly stable against many beta-lactamases produced by Gram-negative microorganisms, allowing it to maintain activity even in the presence of resistance to other antibiotics.

Pharmacological Effects

The drug exhibits an expanded spectrum of activity against Gram-negative flora (E. coli, Proteus, Klebsiella, Enterobacter, Serratia, Citrobacter, Neisseria spp., H. influenzae). A key feature of ceftazidime is its highest activity among third-generation cephalosporins against Pseudomonas aeruginosa.

Indications and Administration

Ceftazidime is prescribed primarily for confirmed infections caused by Pseudomonas aeruginosa.

Dosing Regimen:

Intramuscular: 0.5 g (in 1.5 ml of water) or 1.0 g (in 3 ml of water) every 8 hours.
Intravenous: 0.5 g (in 5 ml of sterile water) administered slowly over 2–4 minutes.

Clinical Considerations

Unlike some other third-generation cephalosporins (e.g., ceftriaxone), ceftazidime requires more frequent administration—every 8 hours. When using the drug, it is important to note that its activity against Gram-positive flora is lower than that of first- and second-generation agents.

Mnemonic

Ceftazidime is the "Blue" (Pseudomonas) leader among third-generation agents.

Frequently asked questions

In which infectious and inflammatory diseases is ceftazidime indicated?

Ceftazidime is used for infections caused by Gram-negative flora, including:

infections caused by Pseudomonas aeruginosa;
leptospirosis during the second wave of fever with multi-organ failure complications;
non-fermenting Gram-negative infections in cystic fibrosis;
infections caused by Achromobacter spp., guided by susceptibility testing;
upper and lower respiratory tract infections and urinary tract infections as part of empirical therapy for febrile neutropenia in settings with low ESBL rates.

What are the absolute contraindications to ceftazidime?

The absolute contraindication to ceftazidime is hypersensitivity to the drug. This restriction is strictly considered when managing non-fermenting Gram-negative infections, including in pregnant patients with cystic fibrosis. If individual intolerance is identified, alternative medications are selected according to institutional clinical protocols.

Does ceftazidime cross the blood-brain barrier?

Yes. Ceftazidime is a third-generation cephalosporin, agents of which cross the blood-brain barrier. Consequently, third-generation cephalosporins are drugs of choice in the treatment of meningitis.

Why is ceftazidime considered the drug of choice for *Pseudomonas* infections?

Among all third-generation cephalosporins, ceftazidime demonstrates the most pronounced antibacterial activity against Pseudomonas aeruginosa.

Can ceftazidime be administered via IV push?

Yes, the drug is administered IV bolus, but slowly over 2–4 minutes, after reconstituting 0.5 g of powder in 5 ml of sterile water.

Which generation of cephalosporins does ceftazidime belong to?

Ceftazidime belongs to the third generation of cephalosporins, which are characterized by high stability against Gram-negative beta-lactamases.

Go deeper

Comparative activity of third-generation cephalosporins against P. aeruginosa.
Mechanisms of resistance to beta-lactam antibiotics.
Pharmacokinetic differences between ceftazidime and ceftriaxone.
Principles of antibiotic selection in Gram-negative meningitis.
Classification of cephalosporins by route of administration (parenteral vs. oral).