Tamiflu ( Oseltamivir ) is indicated for the treatment of uncomplicated acute illness due to influenza infection in patients 1 year and older who have been symptomatic for no more than 2 days.
Tamiflu is also indicated for the prophylaxis of influenza in patients 1 year and older.

Tamiflu is not a substitute for early vaccination on an annual basis as recommended by the Centers for Disease Control and Prevention Advisory Committee on Immunization Practices.

There is no evidence for efficacy of Tamiflu against any illness caused by agents other than influenza types A and B.

Treatment efficacy in subjects with chronic cardiac and/or respiratory disease has not been established. No difference in the incidence of complications was observed between the treatment and placebo groups in this population.

Efficacy of Tamiflu has not been established in immunocompromised patients.

Safety and efficacy of repeated treatment or prophylaxis courses have not been studied.

Influenza can be associated with a variety of neurologic and behavioral symptoms, which can include events such as hallucinations, delirium and abnormal behavior, in some cases resulting in fatal outcomes. These events may occur in the setting of encephalitis or encephalopathy but can occur without obvious severe disease.

There have been postmarketing reports ( mostly from Japan ) of delirium and abnormal behavior leading to injury, and in some cases resulting in fatal outcomes, in patients with influenza who were receiving Tamiflu. Because these events were reported voluntarily during clinical practice, estimates of frequency cannot be made but they appear to be uncommon based on Tamiflu usage data.
These events were reported primarily among pediatric patients and often had an abrupt onset and rapid resolution.

The contribution of Tamiflu to these events has not been established.

Patients with influenza should be closely monitored for signs of abnormal behavior. If neuropsychiatric symptoms occur, the risks and benefits of continuing treatment should be evaluated for each patient.

In postmarketing experience, rare cases of anaphylaxis and serious skin reactions, including toxic epidermal necrolysis, Stevens-Johnson syndrome and erythema multiforme, have been reported with Tamiflu.

In treatment studies in adult patients, the most frequently reported adverse events ( incidence greater than or equal to 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 greater than or equal to 1% ) was vomiting ( 15% ).
Other events reported more frequently in patients taking Tamiflu compared with placebo included abdominal pain ( 5% vs 4% ), epistaxis ( 3% vs 3% ), ear disorder ( 2% vs 1% ) and conjunctivitis ( 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 greater than or equal to 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 prophylaxis trial that included patients 1 to 12 years old, adverse events were consistent with those observed in pediatric treatment studies, with GI events being the most frequently observed.

The concurrent use of Tamiflu with live attenuated influenza vaccine ( LAIV ) intranasal has not been evaluated. However, because of the potential for interference between these products, LAIV should not be administered within 2 weeks before or 48 hours after administration of Tamiflu, unless medically indicated.
Trivalent inactivated influenza vaccine can be administered at any time relative to use of Tamiflu.

Vaccination is considered the first line of defense against influenza.

Source: FDA, 2008

XagenaMedicine2008



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