If you think you have asthma it is important that you make an appointment with your doctor or asthma nurse as soon as possible so that they can do some tests to see if you have asthma. Unfortunately, asthma can't usually be diagnosed with just one test. Doctors and nurses will take a medical history from you to help them look for various clues which will assist them in building up a clinical picture, before reaching a confident diagnosis.
At your appointment you should be asked to do a simple breathing test (lung function test) which measures how quickly you can blow air from your lungs. The test may be done using a hand held 'peak flow meter' device or by blowing into a 'spirometer' which is a small electronic device (this is the preferred device for helping to diagnose asthma). If your readings are low this will help the doctor or asthma nurse in making a diagnosis, but it is important to know that if you have a normal reading you may still have asthma. This is because asthma symptoms are, by nature, variable. For example, you may have a normal reading at the doctor's in the afternoon, but if your appointment had been at 9am that morning it may have been significantly lower.
Trial of treatment
When testing for a diagnosis of asthma, doctors and asthma nurses often prescribe a 'trial of treatment'. This means that you may be given one or more asthma medicines to see if they help the symptoms you are having. If you respond to the treatment, it is a very good indication that you have asthma. If you don't, the medicines won't do you any harm, and the doctor will then have to investigate other possible causes for your symptoms.
A trial of treatment may also be given as part of a 'reversibility test'. Reversibility testing involves taking measurements of your breathing before and after having asthma medicines. If the measurements improve significantly, it is a good indication that you have asthma. There are three medicines that can be used for reversibility testing:
- Inhaled reliever medicine. At your appointment, you may be asked to provide a breathing measurement immediately prior to taking a dose of reliever medicine. Usually this is given from an inhaler device via a spacer. About 20 minutes later you will be asked to provide another measurement.
- Inhaled preventer medicine. You may be asked to provide a breathing measurement at the doctor's, then will be prescribed inhaled preventer medicine to take at home, twice a day, for about 6-8 weeks. You will then return to the doctor who will take another measurement.
- Steroid tablets. You may be asked to provide 'before' and 'after' breathing measurements with a two week course of prednisolone (steroid tablets) in-between. When prescribed for diagnosing purposes, the recommended dose is 30mg prednisolne, taken every morning for two weeks.
The doctor or nurse may also give you a peak flow meter to use at home so you can keep a record of your own peak flow measurements over a period of time.
If you are diagnosed with asthma, the good news is that there are some really effective medicines available to you which means that the symptoms you are currently experiencing can be controlled so they don't bother you any more.
The process of reaching a diagnosis of asthma and getting the correct level of medicine may mean that you need several visits to your doctor or nurse. This is so that they can review the symptoms you are having; see how well any medicine you have been prescribed is helping, check your inhaler technique and help by advising you on how you can control your symptoms better.
With the right care and combination of medicines, the majority of people with asthma can expect to live a normal life, doing all the things they enjoy. Having an asthma action plan will help you achieve this. Research shows that using a plan is one of the most effective ways of controlling asthma. Your doctor or asthma nurse, in discussion with you, should complete this plan. It will contain the information you need to keep control of your asthma, including details about your asthma medicines, how to tell when your symptoms are getting worse and what you should do about it, and emergency information on what to do if you have an asthma attack.