What is the treatment for Influenza B (Influenza type B)?

From the Guidelines

Treatment for influenza B typically involves antiviral medications, rest, and supportive care, with oseltamivir (Tamiflu) being the most commonly prescribed antiviral, taken as 75mg twice daily for 5 days in adults or weight-based dosing for children, as recommended by the most recent guidelines 1. The goal of treatment is to reduce the severity and duration of symptoms, as well as to prevent complications, particularly in high-risk individuals such as the elderly, young children, pregnant women, and people with chronic medical conditions.

• Antiviral medications work best when started within 48 hours of symptom onset, and may include alternative options such as zanamivir (Relenza), peramivir (Rapivab), and baloxavir marboxil (Xofluza) 1.
• Supportive care includes adequate hydration, fever control with acetaminophen or ibuprofen, and rest, with most people recovering within 1-2 weeks without complications.
• Preventive measures like annual vaccination remain the best protection against influenza B infection, and if symptoms worsen, particularly with difficulty breathing, chest pain, or confusion, immediate medical attention is necessary 1. Key considerations in treatment decisions include the patient's disease severity and progression, age, underlying medical conditions, likelihood of influenza, and time since onset of symptoms, with clinical judgment playing an important role in determining the need for antiviral treatment 1.
• The most recent guidelines recommend antiviral treatment as soon as possible for patients with confirmed or suspected influenza who have severe, complicated, or progressive illness or who require hospitalization, as well as for outpatients with confirmed or suspected influenza who are at higher risk for influenza complications on the basis of their age or underlying medical conditions 1.

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. RELENZA, an influenza virus neuraminidase inhibitor (NAI), is indicated for: Treatment of acute, uncomplicated influenza type A and B infections in patients aged 7 years and older who have been symptomatic for no more than 2 days.

The treatment for Influenza B (Influenza type B) is:

• Oseltamivir (PO): for patients 2 weeks of age and older who have been symptomatic for no more than 48 hours 2
• Zanamivir (INH): for patients aged 7 years and older who have been symptomatic for no more than 2 days 3

From the Research

Treatment Options for Influenza B

The treatment for Influenza B (Influenza type B) includes the use of antiviral agents, specifically neuraminidase inhibitors such as zanamivir and oseltamivir 4, 5, 6. These agents are effective against both influenza A and influenza B, and are typically used when started within 24 to 48 hours of onset of symptoms.

Neuraminidase Inhibitors

• Zanamivir and oseltamivir block influenza neuraminidase and prevent the cleavage of sialic acid residues, thus interfering with progeny virus dispersement within the mucosal secretions and reducing viral infectivity 6.
• Oseltamivir has been shown to be effective in reducing the duration of viral shedding and the median area under curve (AUC) virus titre in patients with experimental influenza B virus infection 5.
• Higher-dose oseltamivir treatment has been shown to improve virologic response in patients with influenza B, particularly in those who are hospitalized 7.

Dosage and Administration

• The standard dose of oseltamivir is 75 mg twice daily for 5 days 4, 5.
• Higher doses of oseltamivir, such as 150 mg twice daily, may be used in certain cases, such as in patients with severe influenza B infection requiring organ replacement therapy 7, 8.
• Oseltamivir can be administered orally or intravenously, depending on the patient's condition and ability to absorb the medication 8.

Efficacy and Safety

• Neuraminidase inhibitors have been shown to be effective in reducing the duration and severity of influenza symptoms, particularly when started within 30 hours of symptom onset 6.
• The most common adverse effects of oseltamivir include upper respiratory tract symptoms, headaches, nausea, and vomiting 6.
• Patients with asthma or chronic obstructive pulmonary disease who receive zanamivir may experience an increased incidence of respiratory adverse effects 6.