From the Guidelines
Oseltamivir is indicated for treatment of influenza in patients 2 weeks of age and older, and for prevention of influenza in patients 1 year of age and older, with specific dosing recommendations based on age and weight. According to the most recent guidelines from the American Academy of Pediatrics (AAP) and the Centers for Disease Control and Prevention (CDC) 1, oseltamivir is the preferred antiviral medication for the treatment and prevention of influenza in children. The medication works by inhibiting viral neuraminidase, preventing the release of newly formed virus particles from infected cells, thus limiting viral spread within the respiratory tract.
Key Considerations
- For treatment, the standard adult dose is 75 mg twice daily for 5 days, while pediatric dosing is weight-based:
- 30 mg twice daily for children weighing 15 kg or less
- 45 mg twice daily for 15-23 kg
- 60 mg twice daily for 23-40 kg
- 75 mg twice daily for those over 40 kg
- Treatment is most effective when started within 48 hours of symptom onset
- Common side effects include nausea and vomiting, which can be reduced by taking the medication with food
- For infants younger than 2 weeks, oseltamivir should only be used in critical situations under medical supervision due to limited safety and efficacy data in this age group
Special Populations
- Preterm infants may require lower doses due to immature renal function, and dosing should be based on postmenstrual age (gestational age + chronological age)
- Oseltamivir is not recommended for chemoprophylaxis in infants <3 months due to limited safety and efficacy data in this age group
- For patients with renal insufficiency, the dose should be adjusted based on creatinine clearance
Administration
- Oseltamivir is administered orally or by feeding tube without regard to meals, although administration with meals may improve gastrointestinal tolerability
- The medication is available as a generic drug or as Tamiflu in 30-mg, 45-mg, and 75-mg capsules and as a powder for oral suspension that is reconstituted to provide a final concentration of 6 mg/mL.
From the FDA Drug Label
Oseltamivir phosphate for oral suspension is indicated for the treatment of acute, uncomplicated illness due to influenza A and B infection in patients 2 weeks of age and older who have been symptomatic for no more than 48 hours. Oseltamivir phosphate for oral suspension is indicated for the prophylaxis of influenza A and B in patients 1 year and older.
- Indication for treatment: Oseltamivir is indicated for patients 2 weeks of age and older.
- Indication for prophylaxis: Oseltamivir is indicated for patients 1 year and older. Oseltamivir is not indicated for all ages, as there are specific age restrictions for both treatment and prophylaxis 2.
From the Research
Oseltamivir Indication for All Ages
- Oseltamivir is indicated for the treatment and prophylaxis of influenza in adults and children, including infants 3, 4, 5.
- The medication has been shown to be effective in reducing the duration and severity of symptoms, as well as the risk of complications, in patients with influenza A and B infections 6, 3, 5.
- Oseltamivir is generally well-tolerated, but may cause adverse effects such as nausea, vomiting, and headaches 6, 5, 7.
- The dosage of oseltamivir may need to be adjusted in pediatric patients with renal failure, based on creatinine clearance and body weight 4.
Age-Specific Considerations
- In adults, oseltamivir has been shown to reduce the time to first alleviation of symptoms by 16.8 hours, and to reduce the risk of investigator-mediated unverified pneumonia 5.
- In children, oseltamivir has been shown to reduce the duration of symptoms and the risk of complications, including otitis media and sinusitis 3, 5.
- In infants, oseltamivir has been shown to reduce the duration and severity of symptoms, and to decrease the viral load in nasopharyngeal secretions 3.
Special Populations
- Oseltamivir is approved for use in patients with chronic cardiac and/or respiratory disease, and has been shown to be effective in reducing the duration and severity of symptoms in these patients 6.
- Oseltamivir may be used in pregnant and breastfeeding women, but the benefits and risks should be carefully considered 4, 7.