NI are sialic acid analogs that competitively inhibit neuraminidase on the surface of both influenza A and B, thus interfering with the release of virus from infected cells. Oseltamivir phosphate is an orally bioavailable prodrug that is rapidly absorbed from the gastrointestinal tract and is converted by hepatic esterases to the active metabolite, oseltamivir carboxylate. It has an elimination half-life of approximately 8 h, primarily . These side effects are usually mild and limited to the first days of treatment, although more serious side effects have been described. Oseltamivir has been linked to selfinjury and delirium in pediatric populations, although no causal association could be demonstrated [42, 43] . The use of inhaled zanamivir has been associated with bronchospasm, sometimes severe or fatal, particularly in patients with underlying airways disease such as chronic obstructive pulmonary disease (COPD) or asthma [44] . Amantadine and rimantadine target the M2 protein of influenza A, which forms a proton channel in the viral membrane that is essential for viral replication. Amantadine is primarily excreted unchanged in the urine. In patients older than 65 years and in those with an estimated creatinine clearance of less than 50 mL/min, the daily dose should be reduced. Rimantadine is extensively metabolized in the liver, and dose reduction is recommended for patients with severe hepatic dysfunction, renal failure (creatinine clearance <10 mL/min), and the elderly. Central nervous system (CNS) side effects are well described with amantadine, particularly in elderly patients. In comparison, rimantadine is associated with a considerably reduced rate of CNS side effects [45] .