What is the indication for Tamiflu (Oseltamivir)?

From the Guidelines

Tamiflu (oseltamivir) is indicated for the treatment and prevention of influenza A and B in patients who have been symptomatic for less than 48 hours. For treatment, the standard adult dose is 75 mg twice daily for 5 days, while children receive weight-based dosing, as outlined in the most recent guidelines 1. For prevention, it's given as 75 mg once daily for 10 days following close contact with an infected person. Tamiflu works by inhibiting viral neuraminidase, preventing the release of new virus particles from infected cells, thus reducing viral replication and shortening illness duration by approximately 1-2 days. It's most effective when started within 24-48 hours of symptom onset. Common side effects include nausea, vomiting, and headache. Dose adjustments are necessary for patients with renal impairment. Tamiflu is not a substitute for annual influenza vaccination, which remains the primary method for preventing seasonal influenza. The American Academy of Pediatrics recommends antiviral treatment of any child with influenza who is also at high risk of influenza complications, regardless of vaccination status, and any otherwise healthy child with moderate-to-severe influenza infection who might benefit from the decrease in duration of clinical symptoms documented to occur with therapy 1. The most recent guidelines from 2019 provide the most up-to-date recommendations for the use of oseltamivir in children, including dosage and administration instructions 1. Overall, the use of Tamiflu should be guided by the most recent clinical guidelines and should be considered as part of a comprehensive approach to preventing and treating influenza.

Some key points to consider when prescribing Tamiflu include:

• The importance of starting treatment within 48 hours of symptom onset
• The need for weight-based dosing in children
• The potential for renal impairment to affect dosing
• The importance of annual influenza vaccination as the primary method of prevention
• The potential benefits of treatment in reducing the duration and severity of illness, particularly in high-risk patients.

It is also important to note that the evidence for the efficacy of oseltamivir is based primarily on studies of outpatients with uncomplicated influenza, and that the drug may not be effective in reducing the duration of viral shedding 1. However, the most recent guidelines and studies suggest that oseltamivir can be effective in reducing the duration of illness and preventing complications in certain patient populations, particularly when started early in the course of treatment 1.

In terms of specific patient populations, the guidelines recommend that oseltamivir be used to treat:

• Any child hospitalized with presumed influenza
• Children at high risk for whom influenza vaccine is contraindicated
• Children at high risk during the 2 weeks after influenza immunization
• Influenza infection of any severity in children at high risk of complications of influenza infection. The guidelines also recommend that oseltamivir be used for chemoprophylaxis in certain situations, such as during institutional outbreaks or for close contacts of individuals with influenza.

Overall, the use of Tamiflu should be guided by the most recent clinical guidelines and should be considered as part of a comprehensive approach to preventing and treating influenza.

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.

The indication for Tamiflu (oseltamivir) is:

• 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. 2

From the Research

Tamiflu Indication

• Tamiflu, also known as 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, 5.
• Oseltamivir is also effective in preventing influenza, with a significant reduction in the incidence of influenza when used for seasonal or household prophylaxis 3, 6.
• The drug has been shown to be effective in treating influenza in various populations, including adults, adolescents, children, and high-risk patients such as the elderly and those with chronic cardiac or respiratory disease 3, 7, 4.

Clinical Benefits

• Oseltamivir has been shown to reduce the duration of symptomatic illness, hasten the return to normal levels of activity, and reduce the severity of illness by up to 38% compared with placebo when initiated within 36 hours of symptom onset 3, 7.
• The drug has also been shown to reduce the incidence of secondary complications and the use of antibacterials 3.
• Oseltamivir is well tolerated, with nausea and vomiting being the most commonly reported events, which are mild and transient and can be reduced by taking the drug with food 3, 7.

Special Populations

• Oseltamivir has been shown to be effective in treating influenza in pediatric patients, with a liquid formulation available for children 3.
• The drug has also been shown to be effective in treating influenza in high-risk populations, such as the elderly and those with chronic cardiac or respiratory disease 3, 7.
• Oseltamivir may be used in pregnant women, but the safety and efficacy of the drug in this population have not been extensively studied 6.