The efficacy was highly debated in recent years. The benefits of neuraminidase inhibitors in those who are otherwise healthy do not appear to outweigh its risks. The combination of diagnostic uncertainty, the risk for virus strain resistance, possible side effects and financial cost outweigh the small benefits of oseltamivir or zanamivir for the prophylaxis and treatment of healthy individuals. No benefit of treatment, on hospitalization, complications or risk of death has been found in randomized trials in those people at high risk for complications or the elderly. The United States Centers for Disease Control continues to recommend the use of oseltamavir treatment for people at high risk for complications and the elderly and those at lower risk who present within 48 hours of first symptoms of infection.
Common side effects include nausea and vomiting. For oseltamivir there were neuropsychiatric effects and for zanamivir bronchoconstriction occurred.
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