What medication is used to treat typhoid fever?

Treatment of Typhoid Fever

For typhoid fever, the choice of antibiotic depends critically on local resistance patterns: azithromycin or ceftriaxone are preferred first-line agents in areas with fluoroquinolone resistance (particularly South Asia), while fluoroquinolones remain effective only where organisms are fully susceptible. 1

Antibiotic Selection Algorithm

First-Line Treatment Based on Resistance Patterns:

For Quinolone-Resistant Strains (South Asia, Pakistan XDR outbreak):

• Azithromycin OR Ceftriaxone 1
• Azithromycin shows lower clinical failure rates (OR 0.48) and shorter hospital stays compared to fluoroquinolones, plus lower relapse rates (OR 0.09) compared to ceftriaxone 1

For Fully Susceptible Strains:

• Fluoroquinolones (ciprofloxacin, ofloxacin, gatifloxacin) 1
• Average fever clearance <4 days with cure rates >96% 2

For Multidrug-Resistant Strains:

• Fluoroquinolone or cefixime as alternatives 1

Critical Resistance Caveat:

Do not use ciprofloxacin if the organism is nalidixic acid-resistant, even if reported as "susceptible" on disc testing 2. This requires 10-fold higher doses to maintain adequate MIC and often results in treatment failure. Over 70% of isolates from Asia show fluoroquinolone resistance 2.

Specific Dosing Regimens

Adults:

• Azithromycin: 500 mg PO daily × 7 days 3
• Ceftriaxone: 2-4 g IV daily × 10-14 days 4
• Ciprofloxacin (if susceptible): 500-750 mg PO twice daily × 7-10 days 5

Children:

• Azithromycin: 10-20 mg/kg PO daily × 7 days
• Ceftriaxone: 50-75 mg/kg IV daily (max 4g) × 10-14 days 4
• Ciprofloxacin (if susceptible): 15 mg/kg PO twice daily (max 500-750 mg/dose) 6

Evidence Quality and Nuances

The 2024 WHO guidelines 1 represent the most current recommendations, though they acknowledge that older studies may not reflect current resistance patterns. The Cochrane review 4 found that ceftriaxone may result in decreased clinical failure compared to azithromycin (RR 0.42), though evidence certainty was low. Time to defervescence was 0.52 days shorter with ceftriaxone versus azithromycin.

Important divergence in evidence: While WHO 2012 guidelines 1 list fluoroquinolones as first-line for children, this recommendation predates the widespread emergence of quinolone resistance in South Asia. The 2024 synthesis 1 and recent clinical data 2, 7 clearly indicate azithromycin or ceftriaxone should now be preferred in endemic areas.

Alternative Agents (Historical or Limited Use)

• Chloramphenicol: Re-emerging susceptibility in some areas, but bone marrow toxicity limits use 8, 3
• Ampicillin/Amoxicillin: Only if susceptible; widespread resistance 1
• Trimethoprim-sulfamethoxazole: Only if susceptible; widespread resistance 1
• Cefixime: Oral option but inferior to fluoroquinolones with treatment failure rates 4-37.6% 2, 4

Common Pitfalls

1. Relying on Widal test: Lacks sensitivity and specificity; blood culture is the reference standard 8, 9
2. Using empiric ciprofloxacin without culture: High resistance rates make this inappropriate in most endemic areas 8, 7
3. Inadequate treatment duration: Minimum 7-10 days required; shorter courses increase relapse risk 4
4. Ignoring nalidixic acid resistance: This predicts fluoroquinolone treatment failure despite "susceptible" reporting 2

Treatment Monitoring

Expect fever clearance within 3-5 days with appropriate therapy 2, 4. If fever persists beyond 5-7 days, consider:

• Treatment failure due to resistance
• Complications (intestinal perforation, bleeding, encephalopathy)
• Alternative diagnosis
• Repeat blood cultures and adjust antibiotics based on susceptibility 6