Acute Osteomyelitis & Septic Arthritis

Clinical definition:

Acute osteomyelitis is a bone infection with symptoms lasting days or a few weeks, commonly caused by methicillin-susceptible or resistant S. aureus. Common etiologies of septic arthritis include N. gonorrhea, S. aureus, Streptococcus species, and Gram-negative bacilli.


Preferred antibiotic choice(s)
Drug Formulation Dosage Duration
For the empiric treatment of acute osteomyelitis or septic arthritis:
Cloxacillin (IV) Powder for injection: 500 mg (as sodium salt) in vial. 2 g 6 hourly 4 – 6 weeks
Alternative antibiotic choice(s)
Ceftriaxone (IV) Powder for injection: 250 mg; 1 g (as sodium salt) in vial 1 g daily 4 – 6 weeks
Cefotaxime (IV) Powder for injection: 250 mg per vial (as sodium salt 2 g 8 hourly
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 Amoxicillin component 8 hourly
For the treatment of monoarticular septic arthritis with STD risk
Ceftriaxone (IV) Powder for injection: 250 mg; 1 g (as sodium salt) in vial 1 g daily 2 weeks
In case of confirmed drug allergy or medical contraindication
Clindamycin (IV) Clindamycin- Injection: 150 mg (as phosphate)/mL; Oral liquid: 75 mg/5 mL (as palmitate) 600 mg 8 hourly 2 weeks



Principles of Stewardship:

  • Do not give empirical antibiotics for chronic bone and joint infections. Instead, conduct bone and tissue biopsies, and treat with directed therapy.
  • For septic arthritis, conduct a joint culture before administering antibiotic therapy and refer to an orthopedic surgeon for assessment.
  • If patient cannot take oral antibiotics, start with IV antibiotics and switch to oral therapy as soon as patient is able to take antibiotics orally.


  • Adequate drainage of purulent joint fluid is needed in addition to antibiotic therapy for septic arthritis.