What is the recommended treatment for influenza?

Recommended Treatment for Influenza

The recommended first-line treatment for influenza is oral oseltamivir (Tamiflu) 75 mg twice daily for 5 days in adults, with treatment initiated as soon as possible within 48 hours of symptom onset. 1, 2, 3

Patient Selection for Antiviral Treatment

Antiviral treatment should be prioritized for:

• Hospitalized patients with confirmed or suspected influenza, regardless of illness duration 1
• Outpatients with severe or progressive illness 1
• High-risk patients including:
  • Those with chronic medical conditions or immunocompromised status 1
  • Children younger than 2 years 1
  • Adults ≥65 years 1
  • Pregnant women and those within 2 weeks postpartum 1

Antiviral treatment can also be considered for otherwise healthy individuals not at high risk for complications 1.

Antiviral Medication Options

First-line Treatment

• Oseltamivir (oral): 75 mg twice daily for 5 days in adults 1, 3
  • Pediatric dosing (weight-based):
    • ≤15 kg: 30 mg twice daily
    • 15.1-23 kg: 45 mg twice daily
    • 23.1-40 kg: 60 mg twice daily

    • 40 kg: 75 mg twice daily 2, 3

Alternative Options

• Zanamivir (inhaled): 10 mg (two 5-mg inhalations) twice daily for 5 days 1, 4

  • Not recommended for patients with underlying respiratory disease due to risk of bronchospasm 2, 4
  • Approved for patients ≥7 years 4

• Peramivir (intravenous): Single-dose option for patients who cannot take oral medication 1, 2

• Baloxavir (oral): Single-dose option for patients ≥12 years weighing >40 kg 2

Timing of Treatment

Early initiation of treatment is critical:

• Start treatment as soon as possible, ideally within 48 hours of symptom onset 1, 2
• Earlier treatment (within 12 hours) can reduce illness duration by up to 74.6 hours (3.1 days) compared to starting at 48 hours 5
• For hospitalized patients or those with severe disease, treatment may still be beneficial when started >48 hours after symptom onset 1, 2

Clinical Benefits of Treatment

• Reduces duration of uncomplicated influenza by approximately 1 day 6, 7
• Decreases severity of symptoms by up to 38% when initiated promptly 6
• Reduces risk of complications including otitis media in children by 34% 2
• May reduce risk of pneumonia by approximately 50% 1
• May reduce risk of hospitalization, particularly in high-risk patients 8

Treatment Duration Considerations

• Standard treatment duration is 5 days for uncomplicated influenza 1
• Consider longer treatment duration for:
  • Immunocompromised patients 1
  • Patients hospitalized with severe lower respiratory tract disease 1
  • Patients with persistent viral replication 1

Management of Complications

• Investigate and empirically treat bacterial coinfection in patients with:

  • Severe initial presentation (extensive pneumonia, respiratory failure, hypotension, fever) 1
  • Clinical deterioration after initial improvement 1
  • Failure to improve after 3-5 days of antiviral treatment 1

• Preferred antibiotics for suspected bacterial coinfection:

  • Non-severe pneumonia: oral co-amoxiclav or tetracycline 1
  • Severe pneumonia: intravenous combination of a broad-spectrum β-lactamase stable antibiotic (co-amoxiclav or cephalosporin) with a macrolide 1

Common Pitfalls to Avoid

1. Delaying treatment while waiting for test results: Initiate treatment based on clinical suspicion during influenza season rather than waiting for laboratory confirmation 2

2. Missing the treatment window: The benefit of antiviral treatment diminishes with time; start treatment as soon as possible 5

3. Inappropriate antibiotic use: Avoid antibiotics unless bacterial coinfection is suspected 1, 2

4. Overlooking high-risk patients: Ensure all high-risk patients receive prompt antiviral treatment regardless of illness duration 1

5. Inadequate monitoring: Watch for signs of clinical deterioration that may indicate bacterial coinfection or treatment failure 1

6. Forgetting supportive care: Provide adequate hydration, fever management (avoiding aspirin in children), and rest 1, 2