Zanamivir

About zanamivir

Zanamivir treats gripe (influenza) by preventing the viruses causing the infection from spreading once they are inside your body. This reduces the symptoms of the influenza infection. It also reduces the risk of other problems which can sometimes occur alongside flu, such as pneumonia. It is most effective when it is started within an hour or two of the first symptoms of infection, but it can still be effective after this time, as long as it is started within 48 hours of the first symptoms for adults, or within 36 hours for children.

Zanamivir is also used to prevent flu when there is a flu outbreak in the community, such as in epidemics and pandemics. It is used for those who have been in close contact with people with flu and for those who would be at particular risk if they developed flu (such as children, people with long-term medical conditions, and the elderly). It is most effective when treatment begins as soon as possible after the contact, but it can still be effective when started up to 36 hours afterwards.

Another antiviral medicine called oseltamivir is often prescribed in preference to zanamivir, so you will have been prescribed zanamivir because oseltamivir is not suitable for you for some reason. Zanamivir is not a substitute for seasonal flu vaccination.

Some medicines are not suitable for people with certain conditions, and sometimes a medicine can only be used if extra care is taken. For these reasons, before you start taking zanamivir it is important that your doctor knows:

• If you are pregnant, trying for a baby or breastfeeding. Although you can take zanamivir if you are expecting or feeding a baby, it is important that your doctor knows about this so that you can be made aware of the benefits and any risks of treatment.

• If you have any breathing problems (such as asthma or chronic bronchitis), or if you are using other inhalers.

• If you have ever had an allergic reaction to cow's milk protein. This is different to dairy or lactose intolerance.

• Si está tomando o usando otros medicamentos. Esto incluye cualquier medicamento que esté tomando y que esté disponible para comprar sin receta, así como medicamentos herbales y complementarios.

• Si alguna vez has tenido una reacción alérgica a un medicamento.

• Before you start the treatment, read the manufacturer's printed information leaflet from inside the pack. It will give you more information about zanamivir and provide you with full instructions for using the Diskhaler® with the powder blisters.

• Take zanamivir exactly as your doctor tells you to. It is a powder which is inhaled. The powder is contained in blisters in a foil disc which you load into a Diskhaler®. Your doctor or pharmacist will show you how to use the Diskhaler®.

• Zanamivir is a course of treatment which usually lasts 5-10 days, although it can sometimes be prescribed for up to 28 days during an epidemic. Use the Diskhaler® for as long as your doctor has advised, even if you do not feel unwell. If you have been prescribed it because you already have flu symptoms, you will need to use two inhalations (two blisters) twice-daily for five days, preferably morning and evening. Start using it as soon as possible. If you are taking it because you have been in contact with someone with flu but you do not have any symptoms yourself, then you will need to use two inhalations (two blisters) once a day for at least ten days.

• Try to use the Diskhaler® at the same times each day, as this will help you to take zanamivir regularly.

• Si olvida tomar una dosis, tómela tan pronto como lo recuerde (a menos que esté cerca la hora de su próxima dosis, en cuyo caso omita la dosis olvidada). No tome dos dosis juntas para compensar una dosis olvidada.

• Try to help stop the spread of flu to others. You can do this by remembering to use clean tissues to cover your mouth and nose when you cough and sneeze, binning the tissues after use, and washing your hands regularly with soap and hot water.

• Remember to keep warm, drink plenty of fluids and stay away from crowds. If your symptoms do not improve or they get worse, phone your doctor for further advice.

• If you regularly use other inhalers and these are due at the same time as zanamivir, use your usual inhalers first and then wait a few minutes before you use zanamivir. If you use a reliever inhaler (such as salbutamol) keep this with you while you are using zanamivir, just in case you feel breathless and you need to use it.

Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. The table below contains the most common ones associated with zanamivir. You will find a full list in the manufacturer's information leaflet supplied with your medicine. The unwanted effects often improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any continue or become troublesome.

Si experimenta otros síntomas que cree que pueden deberse al medicamento, hable con su médico o farmacéutico para obtener más consejos.

• Mantenga todos los medicamentos fuera del alcance y la vista de los niños.

• Almacenar en un lugar fresco y seco, lejos del calor y la luz directos.