Synopsis
Choose, dose, review and narrow antibacterial treatment from syndrome severity, likely pathogens, resistance risk, source penetration and patient-specific toxicity rather than habit or drug familiarity.
- Empirical therapy is a reasoned bridge to better information: record syndrome, likely source, severity, organisms covered, route, duration plan and review time.
- Use previous microbiology, recent antibiotics, healthcare or travel exposure, colonisation, immune status and local resistance data to estimate resistant-organism risk.
- Choose the narrowest regimen that safely covers the dangerous plausible pathogens and penetrates the infected compartment; more drugs do not automatically mean better treatment.
Key red flags
Shock, meningitis, neutropenic sepsis or rapidly progressive invasive infection requires prompt syndrome-specific empirical intravenous therapy after feasible cultures.
Investigation priorities
Identify the pathogen and susceptibility while preserving the opportunity to narrow.
Management branches
A bacterial syndrome requires treatment before organism and susceptibility are known.
- Define source, severity and dangerous pathogens; collect high-value cultures and review allergies, weight, organ function, pregnancy, interactions and previous isolates.
- Select route, dose and spectrum from a current national or local syndrome guideline, give time-critical treatment promptly and document indication and review time.
Key medicines
Piperacillin with tazobactamCommon severe-infection adult regimen is 4.5 g intravenously every eight hours; some protocols use every six hours.
GentamicinUse a weight-based once-daily regimen, commonly 5 to 7 mg/kg intravenously, following the local nomogram and levels.