Zanamivir (Relenza) is a new drug, just released in the UK, for the treatment of flu (influenza). It is said, by its manufacturers Glaxo Wellcome, to significantly reduce the severity and duration of flu symptoms. Although it has been licensed to be prescribed by doctors in the UK for this purpose, it has been announced that its use will not immediately be allowed within the National Health Service.

Zanamivir is a powder that is inhaled, twice a day, through a special inhaler. This is used for five days.

The treatment is for use by people over twelve years of age who have Influenza A or Influenza B. It is impossible to be absolutely sure someone has influenza without doing laboratory tests, but these take too long for them to be of any practical value. Therefore, the way in which it is suggested zanamivir is used, is that it be given to people over twelve, who develop "symptoms of 'flu" when influenza is circulating.

There are a number of problems which face doctors, and the British National Health Service:

• Each inhaler costs the NHS £24.
• As mentioned above, it is given to people who might have 'flu. It is likely that many people will seek treatment when they have a bad cold or some other sort of virus or bacterial infection. ie many people will be treated unnecessarily, with something that will not help them.
• Although safety and effectiveness has been shown in trials, we have a significant number of examples of drugs being released to the general public and later being withdrawn. Side effects may only become apparent when millions of people have received the drug.
• Normally the advice is to treat yourself for 'flu. If zanamivir is used, it will mean a massive increase in people visiting their doctors within two days of symptoms starting. In an epidemic, this could overwhelm health services.
• Doctors are likely to want strong evidence that a new drug is more effective than previous treatments, as well as strong evidence of safety, before they will prescribe it to patients.
• The new NHS body responsible for quality and standards (NICE, the National Institute for Clinical Excellence) has been investigating the drug. The British Government have followed advice from NICE and have decided that it will not be available to patients on the NHS.

It may be that this is a useful drug in the treatment of influenza, and the medical world may accept it as the evidence for its use increases. It may even be that the NHS will eventually allow its use. At present, the Minister of Health has called for trials on its use in "at risk groups", before a decision is made on its use in the NHS. It is probable, that if it is, eventually, to be used in the NHS, it will be for a limited number of these "at risk patients" eg the elderly and those with various chronic conditions.

At present, it is likely that the only way to receive this medication in the UK will be by private prescription from a doctor. That is a prescription (which you may have to pay for) which you present to a pharmacy and then you pay the full price for the drug. In such cases it will be up to the individual, having discussed the relative advantages and disadvantages with his or her doctor, to weigh up whether they feel that the possible benefits merit the expense.

Remember, prevention is still an option, and influenza vaccine is available each year (from early October in the UK), and can prevent you from catching influenza. As the old adage goes, prevention is better than cure.

• Medinfo Influenza information.
• UK Health Secretary Dobson tells doctors to shun flu drug (BBC News, 8 Oct 1999) (Original title "Dobson bans flu drug on the NHS")
• Do we really need Relenza? - a doctor comments on a no frills NHS (BBC News, 1 Oct 1999)
• British National Institute for Clinical Excellence
• NICE Guidance - zanamivir (Relenza) in the treatment of influenza (NICE, 8 Oct 1999)
• Glaxo Wellcome Relenza (zanamivir) information
• Relenza approved in the European Union (Glaxo Wellcome press release)
• UK Department of Health