Hospital-Acquired (Nosocomial) Pneumonia (HAP)

Clinical definition:

Pneumonia with onset at least 48 hours following hospital admission excluding ventilator-acquired pneumonia. Early onset HAP is defined as onset within 5 days of admission. Common etiologies of early onset HAP include S. Pneumoniae, S. aureus, H. influenzae, and enteric gram-negative bacilli. Late onset HAP is defined as onset after 5 days following admission; common etiologies include E. coli, S. marcescens, K. pneumoniae, A. baumannii, P. aeruginosa, and Enterobacter species.


Preferred antibiotic choice(s)
For facilities with low-level antibiotic resistance or where resistance is unknown and/or for patients not transferred from facilities with high resistance:
Ceftriaxone (IV)Powder for injection: 250 mg; 1 g (as sodium salt) in vial2 g daily8 days
Cefotaxime (IV)Powder for injection: 250 mg per vial (as sodium salt2 g 8 hourly8 days
Amoxicillin + clavulanic acid (IV)Powder for injection: 500 mg (as sodium) + 100 mg (as potassium salt); 1000

mg (as sodium) + 200 mg (as potassium salt) in vial.

1 g of amoxicillin component 8 hourly8 days
For facilities with high Gram-negative resistance and/or for patients with risk factors for resistance:
Piperacillin-tazobactam (IV)Powder for injection: 2 g (as sodium salt) + 250 mg (as sodium salt); 4 g (as sodium salt) + 500 mg (as sodium salt) in vial4.5 g 8 hourly7 – 14 day
Alternative antibiotic choice(s)
ErtapenemPowder for injection: 1g/vial31 g daily7 – 14 days
In case of confirmed drug allergy or medical contraindication
Moxifloxacin (PO)Tablet: 400 mg; Tablet (dispersible): 100 mg400 mg daily7 – 14 days


Principles of Stewardship:

  • Empiric choice of antibiotics for HAP should be informed by the local resistance profiles in your hospital/unit.
  • It is recommended to obtain both blood and sputum cultures prior to starting antibiotics.
  • Switching from IV antibiotics to oral when patient can tolerate oral medication and as soon as signs and symptoms of infection are improving (e.g. clinical and laboratory white blood cell count improvement).


  • If risk factors for Pseudomonas infection exist, increase dosing frequency of piperacillin-tazobactam to 6 hourly, and use a second-generation carbapenem (e.g., meropenem or imipenem) in place of ertapenem.