Development of oseltamivir resistance in novel H1N1 influenza, though still exceedingly rare, has been reported from several countries [45] . It should be suspected in patients who remain symptomatic or have evidence of viral shedding despite a full treatment course of oseltamivir. Immunosuppression and prior exposure to oseltamivir, such as receipt of prolonged post-exposure prophylaxis, increase the risk for oseltamivir resistance [45] . Zanamivir remains an effective therapeutic option for these cases. Zanamavir is also indicated in the rare circumstance when an oral route for oseltamivir administration is not available for critically ill patients in the intensive care unit. The risk of bronchospam rarely associated with zanamivir, particularly in patients with underlying reactive airway disease, can be minimized by concurrent bronchodilator administration.