What is the recommended treatment for patients presenting with influenza in an urgent care setting?

Treatment of Influenza in Urgent Care Setting

Antiviral treatment with oseltamivir (75 mg twice daily for 5 days) is recommended as soon as possible for patients presenting with influenza in an urgent care setting, ideally within 48 hours of symptom onset. 1, 2

Diagnostic Approach

• Perform rapid influenza virus testing on nasopharyngeal swab or nasal-wash specimens from patients with recent onset of symptoms suggestive of influenza 3
• Consider viral cultures from a subset of patients to determine the infecting virus type and subtype when necessary 3
• Clinical diagnosis may be sufficient for most patients in outpatient settings during influenza season 4

Antiviral Treatment

Adults and Adolescents (≥13 years)

• Oseltamivir 75 mg orally twice daily for 5 days 2
• Start treatment as soon as possible, preferably within 24 hours of symptom onset for maximum benefit 5, 6
• Earlier treatment (within 12-24 hours) can reduce illness duration by up to 3 days compared to starting at 48 hours 6

Children

• Weight-based dosing of oseltamivir for children 1-12 years: 2
  • ≤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

• For children <1 year: 3 mg/kg twice daily 2

Special Populations

• Reduce oseltamivir dose to 75 mg once daily if creatinine clearance is <30 ml/min 1
• Consider treatment for all high-risk patients including those with chronic medical conditions, pregnant women, adults >65 years, and children <2 years 1

Antibiotic Therapy for Suspected Bacterial Co-infection

Consider antibiotics if signs of bacterial co-infection are present:

Adults

• First-line: Doxycycline or co-amoxiclav (amoxicillin-clavulanate) 3, 1
• Alternative (for penicillin allergy): Clarithromycin or erythromycin 3

Children

• First-line: Co-amoxiclav 3
• Alternative (for penicillin allergy): Clarithromycin or cefuroxime 3

Supportive Care

• Acetaminophen or ibuprofen for fever and pain relief 1
• Ensure adequate hydration 1
• Provide oxygen therapy for hypoxic patients (aim for oxygen saturation ≥92%) 1

Infection Control Measures

• Place patients with suspected influenza in a private room 3
• Healthcare personnel should wear a surgical mask when within 3 feet of the patient 3
• Limit patient movement and transport; if necessary, have patient wear a surgical mask 3
• Decontaminate hands before and after patient care 3

Follow-up Recommendations

• Advise patients to return if they experience:
  • Difficulty breathing or shortness of breath
  • Pain or pressure in chest
  • Sudden dizziness or confusion
  • Severe or persistent vomiting
  • Symptoms that improve but then return with fever and worse cough 1

Important Clinical Pearls

1. Timing is critical: The benefit of antiviral treatment is greatest when started within 24 hours of symptom onset 6
2. Consider empiric treatment: During influenza season, consider empiric treatment in high-risk patients without waiting for test results 3
3. Resistance monitoring: Be aware of local antiviral resistance patterns; currently >99% of circulating influenza strains are sensitive to oseltamivir and zanamivir 3
4. Gastrointestinal side effects: Nausea and vomiting can occur with oseltamivir but are typically mild and transient; taking medication with food can improve tolerability 7

Even when treatment is started after 48 hours of symptom onset, oseltamivir may still provide some benefit in reducing symptom duration and viral shedding, particularly in those with severe illness or at high risk for complications 8.