TAMIFLU has not been shown to be effective against any illness other than that caused by influenza types A and B. Efficacy of treatment in patients with chronic cardiac and/or respiratory disease has not been established. No difference in the incidence of complications was seen between the treatment and placebo groups in this population. No information is available regarding treatment of influenza in patients at imminent risk of requiring hospitalization. Efficacy of TAMIFLU has not been established in immunocompromised patients.

Safety and efficacy of repeated courses of TAMIFLU for treatment or prevention have not been studied. In postmarketing experience, rare cases of anaphylaxis and serious skin reactions, including toxic epidermal necrolysis, Stevens-Johnson syndrome and erythema multiforme, have been reported.

There have been postmarketing reports (mostly from Japan) of self-injury and delirium with the use of TAMIFLU in patients with influenza. The reports were primarily among children. The relative contribution of the drug to these events is not known. Patients with influenza should be closely monitored for signs of abnormal behavior throughout the treatment period. In treatment studies in adult patients, the most frequently reported adverse events (incidence ≥ 1%) were nausea and vomiting. Other events reported numerically more frequently in patients taking TAMIFLU compared with placebo were bronchitis, insomnia and vertigo. In treatment studies in patients 1 to 12 years old, the most frequently reported adverse event (incidence ≥ 1%) was vomiting (15%). Other events reported more frequently in patients taking TAMIFLU compared with placebo included abdominal pain (5% vs 4%), nosebleed (3% vs 3%), ear disorder (2% vs 1%) and pinkeye (1% vs < 1%).

In prophylaxis studies in adult patients, adverse events were similar to those seen in the treatment studies. Events reported more frequently in patients taking TAMIFLU compared with placebo (incidence ≥ 1%) were nausea (7% vs 3%), vomiting (2% vs 1%), diarrhea (3% vs 2%), abdominal pain (2% vs 1%), dizziness (1% vs 1%), headache (18% vs 18%) and insomnia (1% vs 1%). In a household prevention trial that included patients 1 to 12 years old, adverse events were similar to those observed in pediatric treatment studies, with GI events being the most common.

The concurrent use of TAMIFLU and live attenuated influenza vaccine (LAIV) intranasal has not been evaluated. However, due to the possibility for interference between these products, LAIV should not be given within 2 weeks before or 48 hours after taking TAMIFLU, unless it is deemed appropriate by your doctor. Trivalent inactivated influenza vaccine can be administered at any time relative to use of TAMIFLU.