Consider the following in selecting the correct antibiotic(s):
1. Host factors — hepatic and renal function
2. Site of infection
3. Antimicrobial sensitivity
4. Drug factors
• Narrow vs wide spectrum, -static vs -cidal, toxicity, costs
Factors limiting antibiotic efficiency include:
1. Poor penetration into site of infection
• Avascular sites
• Diffusion barrier (BBB)
• Intracellular pathogens (TB or Legionella)
2. Obstruction of drainage
• Biliary or GU tracts
3. Presence of foreign body
4. Tissue level factors (acidity)
5. Density of micro-organisms