Typhoid Fever - Injectable (Parenteral) Treatment

1. Ceftriaxone (first-line parenteral agent)

• Adults: 1-2 g IV once daily (up to 2 g twice daily or 4 g once daily in severe disease) for 10-14 days
• Children: 50-75 mg/kg/day (max 2-4 g/day) IV or IM, once or divided into two doses, for 10-14 days
• Outpatient short-course regimens (3-4 g single daily dose for 1-2 days) have shown good efficacy in select uncomplicated cases, though 10-14 days remains standard for confirmed/complicated disease
• Preferred in pregnancy, in areas with drug resistance, and for suspected/confirmed XDR (extensively drug-resistant) S. Typhi (per Red Book 2021 - Committee on Infectious Diseases)

2. Cefotaxime

• Also a first-line IV option for drug-sensitive typhoid, similar dosing principles to ceftriaxone

3. Chloramphenicol (where resistance permits)

• 500 mg IV/IM every 6 hours (adults); children 25 mg/kg IV for 10-14 days
• Largely superseded due to widespread resistance and toxicity concerns, but still used in some resource-limited settings

4. Fluoroquinolones (IV form, e.g., ciprofloxacin)

• Effective against susceptible strains, but fluoroquinolone resistance is increasing globally (per Tintinalli's Emergency Medicine), limiting empiric use

Key clinical points

• Ceftriaxone and fluoroquinolones are associated with the lowest relapse rates (<5%) - Goldman-Cecil Medicine
• For MDR or suspected XDR S. Typhi, empiric parenteral third-generation cephalosporin (ceftriaxone) is recommended pending susceptibility results - Red Book 2021
• Switch to oral therapy once the patient improves clinically and can tolerate oral intake (step-down therapy)
• Relapses are treated with the same antimicrobial regimen used initially

Evidence check