Relenza (Rel-en-za) is a medicine which is used in preventing influenza and treating influenza. Relenza contains zanamivir. It is supplied by GlaxoSmithKline UK.

To get the most benefit from your medicine, take it exactly as prescribed. You should also take care to look after your medicine.

Relenza belongs to a class of medicines called neuraminidase (new-ram-in-id-ayz) inhibitors. It is used to prevent or treat flu.

Flu is caused by a virus called influenza virus. Flu has similar symptoms to a cold but they are usually worse and last longer. The symptoms are usually: fever; blocked and runny nose; cough; sore throat; aches and pains; tiredness; and a general feeling of being unwell. Flu can be a serious illness for elderly people or people who have certain types of medical conditions such as: a weakened immune system; breathing problems like asthma; or heart problems.

The influenza virus gets into the body through the mouth or nose. It makes copies of itself (replicates) in the cells lining the airways ( respiratory tract). The viruses then spread to more and more cells in the airways and this makes the infection more serious. If the virus doesn't spread a lot, the symptoms should be milder and last for a shorter amount of time.

Relenza blocks the effects of a chemical called neuraminidase that is made by the influenza virus. The virus needs neuraminidase to spread in the airways. By blocking the effects of neuraminidase Relenza reduces the spread of the influenza virus in the airways. This makes it easier for the body's immune system to clear-up the infection.

Other information about Relenza:

Do not share your medicine with other people. It may not be suitable for them and may harm them.

The pharmacy label on your medicine tells you how much medicine you should use. It also tells you how often you should use your medicine. This is the dose that you and your prescriber have agreed you should use. You should not change the dose of your medicine unless you are told to do so by your prescriber.

If you feel that the medicine is making you unwell or you do not think it is working, then talk to your prescriber.

Some medicines work best if they are taken at a specific time of day. Getting the most from your medicine can also be affected by what you eat, when you eat and the times at which you take other medicines. Make sure you follow any specific instructions given to you by your prescriber or that are in the Patient Information Leaflet that comes with this medicine.

In the case of Relenza:

Some medicines have specific instructions about how to take them. This is because they work better when taken correctly. These instructions can include getting the right dose and special instructions for preparing the medicine.

In the case of Relenza:

If you are having problems taking this form of Relenza, you should talk to your prescriber or pharmacist. They may be able to give you advice on other ways to take your medicine or other preparations that are easier for you to take.

Taking extra doses of some medicines can be harmful. In some cases even one extra dose can cause you problems. If you take extra doses of your medicine, you must get medical advice immediately. You may need a test to assess the effect of taking extra doses. This is because the effects of taking too much medicine are very complex so it is very important that you seek medical advice.

Contact your prescriber, pharmacist, specialist clinic or NHS Direct on 0845 46 47 for advice.

Make sure you take all of your medicine containers with you if you are advised to go to hospital.

If you are not having any problems with this medicine, do not stop taking it, even if you feel better, unless you have completed the course or you are advised to stop taking it by your prescriber.

If you are in any doubt, contact your prescriber, pharmacist, specialist clinic or NHS Direct on 0845 46 47.

The instructions on how you should keep your medicine are on the pharmacy label. It is a good idea to keep your medicine in the original container. This will help to keep your medicine in the best condition and also allow you to check the instructions. Do not take the medicine if the packaging appears to have been tampered with or if the medicine shows any signs of damage. Make sure that the medicine is out of the sight and reach of children.

In the case of Relenza:

You must not take the medicine after the expiry date shown on the packaging. If you have any unused medicine, return it to your pharmacist who will dispose of it safely.

Your prescriber will not give you this medicine if they know of any reasons why you must not take it. Sometimes it is necessary to prescribe this medicine with extra caution. For more information see the ‘Whether this medicine is suitable for you’ section.

If you have been prescribed this medicine you need to be aware of the side-effects that you could develop while taking this medicine. For more information see the 'Side-effects' section.

Relenza is not suitable for everyone and some people should never use it. Other people should only use it with special care. It is important that the person prescribing this medicine knows your full medical history.

Your prescriber may only prescribe this medicine with special care or may not prescribe it at all if you:

Furthermore the prescriber may only prescribe this medicine with special care or may not prescribe it at all for a child under the age of five years.

As part of the process of assessing suitability to take this medicine a prescriber may also arrange tests:

Over time it is possible that Relenza can become unsuitable for some people, or they may become unsuitable for it. If at any time it appears that Relenza has become unsuitable, it is important that the prescriber is contacted immediately.

Relenza is not suitable for everyone and some people should never use it. Other people should only use it with special care. It is important that the person prescribing this medicine knows your full medical history.

Your prescriber may only prescribe this medicine with special care or may not prescribe it at all if you:

Furthermore the prescriber may only prescribe this medicine with special care or may not prescribe it at all for a child under the age of five years.

As part of the process of assessing suitability to take this medicine a prescriber may also arrange tests:

Over time it is possible that Relenza can become unsuitable for some people, or they may become unsuitable for it. If at any time it appears that Relenza has become unsuitable, it is important that the prescriber is contacted immediately.

A medicine is only made available to the public if the clinical trials have shown that the benefits of taking the medicine outweigh the risks.

Once a medicine has been licensed, information on the medicine's effects, both intended and unintended, is continuously recorded and updated.

Some side-effects may be serious while others may only be a mild inconvenience.

Everyone's reaction to a medicine is different. It is difficult to predict which side-effects you will have from taking a particular medicine, or whether you will have any side-effects at all. The important thing is to tell your prescriber or pharmacist if you are having problems with your medicine.

Very rare: Fewer than 1 in 10,000 people who take Relenza

• allergic reactions
• angioedema of the face or throat
• throat tightness
• skin rash or rashes
• urticaria
• breathing problems or bronchospasm - stop using Relenza and seek immediate medical advice if you develop any breathing problems

The frequency of these side-effects is unknown

• convulsions
• psychiatric problems such as: reduced conscious level; behavioural changes; hallucinations; or delirium - seek medical advice if you get any of these symptoms

If you feel unwell or if you have concerns about a side-effect, you will need to seek advice. If you feel very ill, get medical help straight away. Contact your prescriber, pharmacist, nurse or call NHS Direct on 0845 46 47.

If you have been prescribed this medicine you and your prescriber may need to think about whether you need to change any of your everyday activities. You must also discuss with your prescriber any other medicines and any complementary preparations you are taking.

There are no known important interactions between Relenza and other medicines. If you experience any unusual symptoms while using Relenza and other medicines you should tell your prescriber.

Medicines can interact with complementary preparations and vitamins. In general, there is not much information available about interactions between medicines and complementary preparations or vitamins.

If you are planning to take or are already taking any complementary preparations and vitamins you should ask your prescriber whether there are any known interactions with Relenza.

Your prescriber can advise whether it is appropriate for you to take combinations that are known to interact. They can also discuss with you the possible effect that the complementary preparations and vitamins may have on your condition.

If you experience any unusual effects while taking this medicine in combination with complementary preparations and vitamins, you should tell your prescriber.

When taking any medicine you should be aware that it might interfere with your ability to drive or operate machinery safely.

Like all medicines Relenza can cause side effects. You should see how this medicine affects you and then judge if you are safe to drive or operate machinery. If you are in any doubt, talk to your prescriber.

Medicines can interact with certain foods. In some cases, this may be harmful and your prescriber may advise you to avoid certain foods.

In the case of Relenza:

Alcohol can interact with certain medicines.

In the case of Relenza:

Taking this medicine could have an impact on your decisions relating to family planning, pregnancy and breast-feeding.

Most medicines, in some way, can affect the development of a baby in the womb. The effect on the baby differs between medicines and also depends on the stage of pregnancy that you have reached when you take the medicine.

In the case of Relenza:

You need to discuss your specific circumstances with your doctor to weigh up the overall risks and benefits of taking this medicine. You and your doctor can make a decision about whether you are going to take this medicine during pregnancy.

If the decision is that you should not have Relenza, then you should discuss whether there is an alternative medicine that you could take during pregnancy.

Certain medicines can pass into breast milk and may reach your baby through breast-feeding.

In the case of Relenza:

For information about Relenza and breast-feeding, contact your prescriber.

Medicines contain active ingredients. They may also contain other, additional ingredients that help ensure the stability, safety and effectiveness of the medicine. They are also added to improve the medicine's taste and appearance and to make it easier to take. Some may be used to prolong the life of the medicine.

You should check that you are able to take the ingredients in your medicine, especially if you have any allergies.

Relenza contains:

If you are not able to take any of the ingredients in your medicine, talk to your prescriber or pharmacist to see if they can suggest an alternative medicine. If you have reacted badly to Relenza before, do not take Relenza. Talk to your prescriber, pharmacist or nurse as soon as possible.