Ceftazidime + avibactam !

Ceftazidime protected by avibactam, a non-β-lactam inhibitor active against KPC and OXA-48; reserved for resistant gram-negatives.

Updated 2026-11-01

Class: Beta-lactams
Enzyme: Bacterial PBPs (ceftazidime) and class A, C and some class D β-lactamases (avibactam)
ATC code: J01DD52
WHO Model List of Essential Medicines

Also called: ceftazidime–avibactam

Bacterial PBPs (ceftazidime) and class A, C and some class D β-lactamases (avibactam)Ceftazidime + avibactam

The figure shows avibactam covalently bound to the KPC-2 carbapenemase of Klebsiella pneumoniae.

Target in 3D: Bacterial PBPs (ceftazidime) and class A, C and some class D β-lactamases (avibactam). PDB structure 4ZBE (RCSB PDB, public domain). View the structure at RCSB PDB

Mechanism of action

Ceftazidime acylates the PBPs of gram-negatives, including Pseudomonas aeruginosa. Avibactam is a non-β-lactam β-lactamase inhibitor, active against Ambler class A enzymes, including KPC carbapenemases, class C (AmpC) and some class D enzymes such as OXA-48. It does not inhibit metallo-β-lactamases (class B, such as NDM), so it fails against those strains.

Avibactam binds the serine of KPC, AmpC or OXA-48
The β-lactamase is inhibited and cannot destroy ceftazidime
Ceftazidime acylates the gram-negative PBP3
The bacterium cannot build its septum and lyses

Pharmacokinetics

Absorption: Intravenous only.
Elimination: Both components by the kidney; adjusted in kidney failure.

Indications

Complicated intra-abdominal infections, with metronidazole. Peritonitis →
Complicated urinary tract infections, including pyelonephritis. Acute pyelonephritis →
Hospital-acquired and ventilator-associated pneumonia.

Adverse effects

Common

Nausea, vomiting, diarrhoea, constipation
Abdominal pain, dizziness, headache

Contraindications

Serious hypersensitivity to any component or to other β-lactams

Key interactions

Probenecid: Reduces tubular secretion: higher and longer-lasting β-lactam levels.

What is monitored

Creatinine (dose adjustment)
Cultures and carbapenemase type (KPC, OXA-48 or metallo-β-lactamase)

Administration and safety

Intravenous infusion only.
Do not confuse with plain ceftazidime: the spectrum differs.
It is reserved for resistant gram-negative infections under the antimicrobial stewardship programme.

Nursing care

Before the first dose: ask about allergy to penicillins, cephalosporins and other β-lactams, and what the reaction was.
Monitor creatinine and urine output.
Teach the patient to report watery or bloody diarrhoea, even weeks after the course ends.

Pregnancy and breastfeeding

Data in pregnant women are limited; it is used only if the benefit justifies the risk, and the team is told about any pregnancy.

Test yourself

Think of the answer, then tap the question to see it.

Which β-lactamases does avibactam inhibit, and which not?

It inhibits class A (including KPC), class C (AmpC) and some class D such as OXA-48; it does not inhibit metallo-β-lactamases (class B).

What chemically sets avibactam apart from clavulanic acid or tazobactam?

It is not a β-lactam, whereas the traditional inhibitors resemble β-lactams; it also covers β-lactamase classes they do not inhibit.

Which drug is it combined with in intra-abdominal infections, and why?

With metronidazole, to cover anaerobes.

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Educational content on how drugs work; not a prescribing guide and no substitute for a health professional's advice. No doses are given.

Sources: Ceftazidime and Avibactam Injection: MedlinePlus Drug Information (MedlinePlus (U.S. National Library of Medicine), 2026); RCSB PDB - 4ZBE: Crystal structure of KPC-2 beta-lactamase complexed with avibactam (RCSB Protein Data Bank, 2026); Farmacología básica y clínica (Katzung), cap. 43 (McGraw Hill, 2025).

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Representative model, for educational purposes only.