Skip to Content

Relenza FDA Alerts

The FDA Alerts below may be specifically about Relenza or relate to a group or class of drugs which include Relenza.

MedWatch Safety Alerts are distributed by the FDA and published by Following is a list of possible medication recalls, market withdrawals, alerts and warnings.

Jump to date

Recent FDA Alerts for Relenza

Relenza (zanamivir) Inhalation Powder

[Posted 10/09/2009] GlaxoSmithKline (GSK) and FDA notified healthcare professionals of a report of the death of a patient with influenza who received Relenza (zanamivir) Inhalation Powder which was solubilized and administered by mechanical ventilation. Relenza (zanamivir) Inhalation Powder is not intended to be reconstituted in any liquid formulation and is not recommended for use in any nebulizer or mechanical ventilator.

GSK is aware that Relenza Inhalation Powder is being removed from its FDA-approved packaging and dissolved in various solutions for the purpose of nebulizing zanamivir for inhalation by patients with influenza who are unable to take oral medications or unable to inhale Relenza Inhalation Powder using the Diskhaler. Relenza or zanamivir for nebulization have not been approved by the FDA. The safety, effectiveness, and stability of zanamivir use by nebulization have not been established.

Relenza Inhalation Powder should only be used as directed in the prescribing information by using the Diskhaler device provided with the drug product. Relenza Inhalation Powder is a mixture of zanamivir active drug substance and lactose drug carrier. This formulation is not designed or intended to be administered by nebulization. There is a risk that the lactose sugar in this formulation can obstruct proper functioning of mechanical ventilator equipment.

Relenza (zanamivir)

[Posted 04/01/2008] GlaxoSmithKline informed healthcare professionals of changes to the WARNINGS AND PRECAUTIONS sections of prescribing information for Relenza regarding information from postmarketing reports (mostly from Japan) of delirium and abnormal behavior leading to injury in patients with influenza who are receiving neuraminidase inhibitors, including Relenza. These events were reported primarily among pediatric patients and often had an abrupt onset and rapid resolution. The contribution of Relenza to these events has not been established. Influenza can be associated with a variety of neurologic and behavioral symptoms which can include seizures, 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.

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.

[March, 2008 - Letter - GlaxoSmithKline]

More Relenza Resources