From the Guidelines
Tamiflu (oseltamivir) should be taken as prescribed by a healthcare provider, typically within 48 hours of flu symptom onset for maximum effectiveness, with the standard adult dose being 75 mg twice daily for 5 days, and weight-based dosing for children, as outlined in the 2019 Pediatrics guidelines 1. The guidelines for the use of Tamiflu (oseltamivir) are as follows:
- Start treatment as soon as possible after symptoms begin, as early therapy provides the best outcomes 1
- Complete the full course of medication, even if symptoms improve, to ensure maximum effectiveness
- Take with or without food, but taking with food may reduce nausea, as administration with meals may improve gastrointestinal tolerability 1
- For prevention, use as directed when exposed to flu (usually 75 mg once daily for at least 10 days), with the CDC recommending 7 days and 10 days only if part of an institutional outbreak 1 Key considerations for Tamiflu use include:
- Dosage adjustments for patients with renal insufficiency, with the dose adjusted on the basis of creatinine clearance 1
- Contraindications for infants <3 months old due to limited safety and efficacy data in this age group 1
- Special considerations for preterm infants, with lower weight-based dosing recommendations due to immature renal function 1
- Potential side effects, including nausea and vomiting, which occur in approximately 5% of treated patients, and rare but serious side effects like behavioral changes, which should be reported to a doctor immediately 1 Overall, Tamiflu (oseltamivir) can shorten the duration of flu symptoms by 1-2 days and may reduce the risk of complications, but it is not a substitute for the flu vaccine, and its use should be guided by clinical judgment and consideration of the balance between benefits and harms 1.
From the FDA Drug Label
Oseltamivir phosphate for oral suspension is an influenza neuraminidase inhibitor (NAI) indicated for: Treatment of acute, uncomplicated influenza A and B in patients 2 weeks of age and older who have been symptomatic for no more than 48 hours. Prophylaxis of influenza A and B in patients 1 year and older.
DOSAGE AND ADMINISTRATION Treatment of influenza Adults and adolescents (13 years and older): 75 mg twice daily for 5 days Pediatric patients 1 to 12 years of age: Based on weight twice daily for 5 days Pediatric patients 2 weeks to less than 1 year of age: 3mg/kg twice daily for 5 days
Prophylaxis of influenza Adults and adolescents (13 years and older): 75 mg once daily for at least 10 days Community outbreak: 75 mg once daily for up to 6 weeks Pediatric patients 1 to 12 years of age: Based on weight once daily for 10 days Community outbreak: Based on weight once daily for up to 6 weeks
The guidelines for the use of Tamiflu (Oseltamivir) are as follows:
- Treatment: Oseltamivir is indicated for the treatment of acute, uncomplicated influenza A and B in patients 2 weeks of age and older who have been symptomatic for no more than 48 hours.
- Prophylaxis: Oseltamivir is indicated for the prophylaxis of influenza A and B in patients 1 year and older.
- Dosage:
- Treatment: + Adults and adolescents (13 years and older): 75 mg twice daily for 5 days + Pediatric patients 1 to 12 years of age: based on weight twice daily for 5 days + Pediatric patients 2 weeks to less than 1 year of age: 3mg/kg twice daily for 5 days
- Prophylaxis: + Adults and adolescents (13 years and older): 75 mg once daily for at least 10 days + Community outbreak: 75 mg once daily for up to 6 weeks + Pediatric patients 1 to 12 years of age: based on weight once daily for 10 days + Community outbreak: based on weight once daily for up to 6 weeks 2
From the Research
Guidelines for the Use of Tamiflu (Oseltamivir)
The guidelines for the use of Tamiflu (Oseltamivir) are as follows:
- Oseltamivir is indicated for the treatment of uncomplicated influenza in patients two weeks of age or older who have been symptomatic for no more than two days 3, 4.
- The recommended dosage is 75 mg twice daily by mouth for five days 3, 4.
- Oseltamivir can also be used for seasonal or household prophylaxis, with a dosage of 75 mg once or twice daily for 6 weeks 3.
- For children, a liquid formulation of oseltamivir (2 mg/kg twice daily for 5 days) has been shown to be effective in the treatment of influenza 3.
- Oseltamivir is well tolerated, with nausea and vomiting being the most commonly reported events, which can be reduced by taking the medication with food 3, 5.
Special Populations
- In high-risk populations, such as the elderly or those with chronic cardiac or respiratory disease, oseltamivir has been shown to be effective in reducing the duration and severity of illness 3, 5.
- In pediatric patients, oseltamivir has been shown to be effective in reducing the intensity of influenza symptoms and the number of days of hospitalization 6.
- In patients with comorbidities, such as asthma, gastrointestinal diseases, and metabolic and endocrine diseases, oseltamivir has been shown to be effective in reducing the duration and severity of illness 6.
Off-Label Use
- There is limited evidence to support the use of oseltamivir outside of labeled recommendations, such as administering the drug 48 hours or more after the onset of influenza symptoms, or continuing therapy for more than five days 4.
- However, some studies suggest that oseltamivir may be effective in reducing the duration and severity of illness in certain patient populations, such as those with influenza H1N1 infection who require ICU admission 4.