Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.
Asthma or breathing disorders: This medication can cause serious breathing problems (wheezing, difficulty breathing). If you do take this medication and you have asthma or COPD, make sure you have your fast-acting bronchodilator available. If your dosing schedule requires both your bronchodilator and zanamivir to be used at the same time, use your bronchodilator first.
If you develop worsening breathing problems such as difficulty breathing, shortness of breath, or wheezing, stop using zanamivir and contact your doctor as soon as possible. Zanamivir is generally not recommended for people with a history of breathing disorders (e.g., asthma, COPD).
Effectiveness: The benefit of zanamivir has not been seen for the treatment of flu symptoms that have been present for more than 2 days.
Flu shots: Zanamivir is not a substitute for the flu shot. Continue to receive an annual flu shot as advised by your doctor.
Mental health: There have been reports of people who experienced delirium and abnormal behaviour while taking zanamivir. The exact link between zanamivir and these behaviours have not been established. If you experience any changes in behaviour, contact your doctor as soon as possible.
Pregnancy: This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking this medication, contact your doctor immediately.
Breast-feeding: It is now known if zanamivir passes into breast milk. If you are a breast-feeding mother and are taking this medication, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.
Children: The safety and effectiveness of using this medication have not been established for children under 7 years of age.