What is the treatment for a 15-year-old patient with influenza (flu) lasting 4 days?

From the Guidelines

For a 15-year-old who has had the flu for 4 days, the primary focus should be on supportive care, including rest, adequate hydration, and fever control with acetaminophen or ibuprofen, as antiviral medications like oseltamivir are typically less effective when started more than 48 hours after symptom onset 1.

Key Considerations:

• Ensure the patient drinks plenty of fluids like water, clear broths, or electrolyte solutions to prevent dehydration.
• Use acetaminophen (325-650 mg every 4-6 hours, not exceeding 3,000 mg daily) or ibuprofen (200-400 mg every 6 hours with food, not exceeding 1,200 mg daily) for fever control.
• Monitor for warning signs that require immediate medical attention, such as difficulty breathing, chest pain, persistent vomiting, confusion, or worsening symptoms after initial improvement.
• The patient should stay home from school until fever-free for at least 24 hours without fever-reducing medication to prevent spreading the virus to others.

Antiviral Treatment:

• According to the guidelines, antiviral treatment with oseltamivir, zanamivir, or peramivir should be started as soon as possible, ideally within 48 hours of symptom onset, for the best outcomes 1.
• For a 15-year-old, the recommended dosage of oseltamivir for treatment is 75 mg, twice daily for 5 days, as indicated in the guidelines 1.

Important Notes:

• The effectiveness of antiviral medications decreases when started more than 48 hours after symptom onset, but they may still be considered in patients with severe disease or those at high risk of complications 1.
• The decision to use antiviral treatment should be based on clinical judgment, considering factors such as disease severity, time since symptom onset, and local influenza activity 1.

From the FDA Drug Label

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice Assessment of adverse reactions is based on a randomized, active-controlled study in which 130 adolescent and pediatric subjects ages 6 months to 17 years of age with acute uncomplicated influenza received open-label treatment with a single dose of RAPIVAB (n = 107), or 5 days of treatment with oseltamivir (n = 23) The safety profile of RAPIVAB in subjects 6 months to 17 years of age was generally similar to that observed in adults.

For a 15-year-old who has had the flu for 4 days, peramivir (IV) can be considered as a treatment option.

• The safety profile of peramivir in adolescent and pediatric subjects (6 months to 17 years of age) was generally similar to that observed in adults.
• However, it is essential to closely monitor the patient for signs of abnormal behavior, as there have been postmarketing reports of delirium and abnormal behavior leading to injury in patients with influenza who were receiving neuraminidase inhibitors, including peramivir 2.
• Additionally, prescribers should be alert to the potential for secondary bacterial infections and treat with antibiotics as appropriate.

From the Research

Treatment Options for a 15-Year-Old with the Flu

• The treatment for a 15-year-old who has had the flu for 4 days may involve the use of antiviral medications such as zanamivir and oseltamivir 3, 4.
• These medications work by inhibiting the viral neuraminidase enzyme, which is responsible for the release of newly formed virions from the host cell, thereby limiting the extent of infection and speeding up recovery 3, 4.
• Clinical studies have shown that neuraminidase inhibitors can decrease the median duration of influenza-related symptoms by approximately 1 day if initiated within 48 hours of the onset of symptoms of influenza 3, 4.

Efficacy of Oseltamivir in Infants

• A study on the treatment of influenza A and B infections in infants found that oseltamivir treatment rapidly decreased the viral load in nasopharyngeal secretions and shortened the duration and severity of symptoms 5.
• The study found that the mean total duration of illness in oseltamivir recipients was significantly shorter than in infants without treatment, with a mean duration of 82.1 hours for influenza A and 110.0 hours for influenza B 5.

Comparison of Neuraminidase Inhibitors

• A study comparing the clinical effects of oseltamivir, zanamivir, laninamivir, and peramivir on seasonal influenza infection in outpatients in Japan found that peramivir alleviated fever and other symptoms significantly sooner than zanamivir and oseltamivir 6.
• Another study found that inhaled zanamivir was not inferior to oral oseltamivir in preventing influenza-related hospitalization or death in outpatients 7.

Considerations for Treatment

• The choice of treatment may depend on various factors, including the severity of symptoms, the presence of underlying medical conditions, and the patient's age and weight 3, 4.
• It is essential to initiate treatment within 48 hours of the onset of symptoms to maximize the effectiveness of the medication 3, 4.