NICE Guidance on the use of zanamIvir (Relenza) for the treatment of influenza

1. Introduction

Zanamivir (Relenza) is a neuraminidase inhibitor that is licensed for the treatment of influenza in individuals over 12 years of age. For at-risk adults zanamivir has been shown to reduce the duration of symptoms by around one day and reduce the absolute rate of complications requiring antibiotics by 6% 1.

NICE has recently reviewed its guidance on the use of zanamivir for the treatment of influenza and has outlined the circumstances in which they recommend that it is prescribed. This bulletin aims to offer practical advice on the use of zanamivir during an outbreak of ‘flu.

2. NICE Guidance

Zanamivir should NOT be prescribed for people with the symptoms of ‘flu who are otherwise healthy. (Symptoms are only reduced by around 24 hours in this group).

Immunisation is the first line defence against influenza for at-risk patients.

Zanamivir is recommended for at-risk patients ONLY when practitioners have been informed that influenza is known to be circulating in the community.

When ‘flu is circulating, zanamivir may be prescribed for at-risk adults who present within 36 hours of the start of influenza like symptoms and are able to begin treatment within 48 hours The at-risk groups are defined as:

Most people with ‘flu like symptoms do not require special treatment. Antibiotics should not be prescribed unless there are complications. Patients should be advised to stay at home if feeling ill, rest and drink plenty of fluids. Simple analgesics available "over the counter" may be taken.

 3. Implementation

3.1 Notification of influenza

Practitioners need to be informed when influenza is circulating in the community 2. This information will be cascaded to practices by the HA Influenza Co-ordinator, Dr. G. Double (Tel: 0208 532 6376). Information will also be posted on the DOH website www.doh.gov.uk/flu.

This system will also be used to notify practices when ‘flu levels fall below the threshold required to trigger prescribing of zanamivir according to NICE guidance.

3.2 Management of at-risk groups in primary care

Practices should ensure that at-risk patients have been immunised against influenza by the end of December.

Only patients who are in the at-risk groups, and who are able to start treatment within 48 hours of developing symptoms, should be offered zanamivir. To assist this process, practices may wish to consider:

The fact that zanamivir should be administered within 48 hours of developing symptoms, could place pressure on clinicians to supply the drug before a proper medical assessment has been made. Whilst eligible patients should be offered treatment with zanamivir, clinicians should not be distracted from the overall management of the patient by pressure to supply a particular treatment.

For patients who cannot start zanamivir within the 48 hour window, clinicians are advised to monitor for complications and prescribe antibiotics where appropriate to treat secondary infections. It is equally important to monitor patients who have been prescribed zanamivir, as most will still be at risk of developing complications.

3.3 Management of non at-risk groups

The HA will be encouraging patients with influenza like illness to contact their pharmacist or NHS Direct for advice in the first instance. Patients who are not eligible for treatment with zanamivir will be advised on self-care.

Information leaflets "What to do about flu?" are available from the Department of Health, PO Box 777, London SE1 6XH. Tel: 0541 555 455 (Ref: 22605) www.nice.org.uk

3.4 Out of hours services

The above advice applies to the out of hours service. At-risk patients should only be prescribed zanamivir if they are able to commence treatment within 48 hours of onset of symptoms.

Patients should NOT be referred to A&E as a means of receiving zanamivir quickly. During an outbreak of ‘flu, A&E will be managing patients with severe complications and will not routinely supply zanamivir.

 

The protocol for nurse triage is available on the DOH website www.doh.gov.uk/zanamavirguidance/triage.pdf

 

ZANAMIVIR (RELENZA)

Please refer to the manufacturer’s Summary of Product Characteristics for full details.

Indications

Relenza is indicated for the treatment of influenza A and B in adults and adolescents (>12 years) showing symptoms typical of influenza when influenza is circulating in the community.

Dose

Two inhalations (2x5mg) twice a day for 5 days using the Diskhaler device provided. One blister should be utilised for each inhalation. Commence treatment within 48 hours of onset of symptoms. Inhaled drugs (e.g. asthma medication) should be administered prior to administration of Relenza.

No dose adjustment is required for elderly patients or those with impaired renal or hepatic function.

Children: Not recommended.

Special precautions

Warn patients with asthma or COPD of bronchospasm risk and need for fast acting bronchodilator to be on hand. The use of zanamivir is not recommended during pregnancy or in mothers who are breast-feeding.

Adverse Drug Reactions

Rarely acute bronchospasm, decline in respiratory function (withdraw immediately).

t Report any adverse reaction to the CSM.

Drug Interactions

Clinically significant drug interactions are unlikely. Zanamivir has not been shown to impair the immune response for influenza vaccine.

Instructions for use

The Diskhaler is loaded with a disk containing inhalation powder packed in individual blisters. These blisters are pierced when the inhaler is used, and with deep inhalation the powder can then be inhaled through the mouthpiece down into the respiratory tract. Detailed instructions for use are enclosed in the pack.

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Prescribing Strategy Group - December 2000

 

1NICE technology appraisal no.15.

2When the PHLS advise that they have identified a circulation of the virus and the RCGP weekly returns service monitoring data indicate that new consultations for influenza-like illness >50/100,000 population per week.