Cefotaxime !

A third-generation intravenous cephalosporin that crosses inflamed meninges; used for meningitis and sepsis, including in newborns.

Updated 2026-11-01

Class: Beta-lactams
Enzyme: Penicillin-binding proteins (bacterial transpeptidases)
ATC code: J01DD01
WHO Model List of Essential Medicines

Penicillin-binding proteins (bacterial transpeptidases)Cefotaxime

The figure shows Streptococcus pneumoniae PBP1b acylated by cefotaxime; the ligand is the bound form, which loses its 3' group.

Target in 3D: Penicillin-binding proteins (bacterial transpeptidases). PDB structure 2XD1 (RCSB PDB, public domain). View the structure at RCSB PDB

Mechanism of action

Cefotaxime acylates the PBPs and blocks wall synthesis. It is stable to many β-lactamases and very active against pneumococci, meningococci, Haemophilus influenzae, gonococci and enteric bacteria. Its desacetyl metabolite is also bactericidal. It does not cover Listeria, enterococci or Pseudomonas, and ESBLs hydrolyse it.

Reaches the cerebrospinal fluid when the meninges are inflamed
Acylates the PBPs of pneumococci, meningococci and Haemophilus
Peptidoglycan cross-linking stops
The bacterium lyses

Pharmacokinetics

Absorption: Intravenous or intramuscular.
Metabolism: Partly converted to desacetylcefotaxime, an active metabolite.
Elimination: By the kidney.
Half-life: About 1 hour in adults; longer in low-birth-weight newborns.

Indications

Meningitis and ventriculitis due to meningococci, H. influenzae, pneumococci or enteric bacteria; in newborns, with ampicillin. Bacterial meningitis →
Septicaemia. Sepsis and septic shock →
Lower respiratory tract infections, including pneumonia. Community-acquired pneumonia →
Gonorrhoea. Gonorrhoea →
Urinary tract infections due to susceptible gram-negatives. Urinary tract infection (acute cystitis) →

Adverse effects

Common

Pain, hardening and phlebitis at the injection site
Rash, itching, fever
Diarrhoea, nausea

Contraindications

History of hypersensitivity to this or another cephalosporin; caution, and sometimes contraindication, after anaphylaxis to penicillins or other β-lactams

Key interactions

Probenecid: Reduces tubular secretion: higher and longer-lasting β-lactam levels.
Aminoglycosides: They can be combined, but kidney function is monitored because of aminoglycoside kidney and ear toxicity.

What is monitored

Kidney function
Clinical response and cerebrospinal fluid cultures in meningitis

Administration and safety

Intravenous or intramuscular.
Never as a rapid bolus through a central line: serious arrhythmias have been reported; it is injected slowly or infused.
Do not confuse cefotaxime with cefoxitin or ceftriaxone.

Nursing care

Before the first dose: ask about allergy to penicillins, cephalosporins and other β-lactams, and what the reaction was.
Monitor heart rhythm when given centrally.
Check the injection site for phlebitis.
Teach the patient to report watery or bloody diarrhoea, even weeks after the course ends.

Pregnancy and breastfeeding

Animal studies showed no fetal harm and there are no controlled studies in pregnant women; used if clearly needed.

Test yourself

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

Which cefotaxime metabolite contributes to its effect?

Desacetylcefotaxime, its main metabolite, which is also bactericidal and is cleared by the kidney.

What is the risk of giving cefotaxime as a rapid bolus through a central line?

Potentially fatal arrhythmias; it is given slowly or as an infusion.

Which drug is added to cefotaxime for neonatal meningitis, and why?

Ampicillin, to cover Listeria monocytogenes (and enterococci), which do not respond to cephalosporins.

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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: Cefotaxime Injection: MedlinePlus Drug Information (MedlinePlus (U.S. National Library of Medicine), 2026); DailyMed - CEFOTAXIME injection, powder, for solution (DailyMed (U.S. National Library of Medicine), 2026); RCSB PDB - 2XD1: ACTIVE SITE RESTRUCTURING REGULATES LIGAND RECOGNITION IN CLASS A PENICILLIN-BINDING PROTEINS (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.