Zanamivir

Due to the limited experience, patients with severe asthma require a careful consideration of the risk in relation to the expected benefit, and zanamivir should not be administered unless close medical monitoring and appropriate clinical facilities are available in case of bronchoconstriction. In patients with persistent asthma or severe COPD, management of the underlying disease should be optimised during therapy with zanamivir.

Should zanamivir be considered appropriate for patients with asthma or chronic obstructive pulmonary disease, the patient should be informed of the potential risk of bronchospasm with zanamivir and should have a fast acting bronchodilator available. Patients on maintenance inhaled bronchodilating therapy should be advised to use their bronchodilators before taking zanamivir.

Neuropsychiatric events have been reported during administration of zanamivir in patients with influenza, especially in children and adolescents. Therefore, patients should be closely monitored for behavioural changes and the benefits and risks of continuing treatment should be carefully evaluated for each patient.

Systemic exposure to zanamivir is low following administration by inhalation; however, there is no information on placental transfer of zanamivir in humans. There is a limited amount of data (less than 300 pregnancy outcomes) from the use of zanamivir in pregnant women. Animal studies do not indicate direct or indirect harmful effects with respect to reproductive toxicity.

As a precautionary measure, it is preferable to avoid the use of zanamivir during pregnancy, unless the clinical condition of the woman is such that the potential benefit to the mother significantly outweighs the possible risk to the foetus.

Systemic exposure to zanamivir is low following administration by inhalation; however, there is no information on secretion of zanamivir into human breast milk. A risk to the breastfed child cannot be excluded. A decision must be made whether to discontinue breast-feeding or to discontinue/abstain from zanamivir therapy, taking into account the benefit of breast feeding for the child and the benefit of therapy for the woman.

Fertility

Animal studies indicate no clinically meaningful effects of zanamivir on male or female fertility.

Zanamivir has no or negligible influence on ability to drive and use machines.

There have been rare reports of patients with previous history of respiratory disease (asthma, COPD) and very rare reports of patients without previous history of respiratory disease, who have experienced acute bronchospasm and/or serious decline in respiratory function after use of zanamivir.

The adverse events considered at least possibly related to the treatment are listed below by body system, organ class and absolute frequency. Frequencies are defined as very common (≥1/10), common (>1/100, <1/10), uncommon (>1/1000, <1/100), rare (≥1/10,000, <1/1000), very rare (<1/10,000), not known (cannot be estimated from the available data).

Within each frequency grouping, undesirable effects are presented in order of decreasing seriousness.

Immune system disorders

Uncommon: allergic-type reactions including oropharyngeal oedema

Rare: anaphylactic/Anaphylactoid reactions, facial oedema

Nervous systems disorders

Uncommon: vasovagal-like reactions have been reported in patients with influenza symptoms, such as fever and dehydration, shortly following inhalation of zanamivir.

Respiratory, thoracic and mediastinal disorders

Uncommon: bronchospasm, dyspnea, throat tightness or constriction

Skin and subcutaneous tissue disorders

Common: rash

Uncommon: urticaria

Rare: severe skin reactions including Erythema Multiforme, Stevens-Johnson syndrome and Toxic epidermal necrolysis

Psychiatric and nervous system disorders

Convulsions and psychiatric events such as depressed level of consciousness, abnormal behaviour, hallucinations and delirium have been reported during zanamivir administration in patients with influenza. The symptoms were mainly reported in children and adolescents. Convulsions and psychiatric symptoms have also been reported in patients with influenza not taking zanamivir.