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Asthma Health Center

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Diagnosing Asthma

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Diagnosing Asthma and Asthma Tests continued...

For more information, see WebMD's Pulmonary Function Tests.

Peak Flow Testing -- a self-assessment you can do at home to evaluate lung function. The peak expiratory flow rate (PEFR) provides a reliable objective measure of airway function. Your doctor will go over how to use a peak flow meter, which involves taking a deep breath and blowing out as hard as you can. Peak flow is the highest airflow velocity that you can achieve. When done accurately, a drop in the peak flow measurement reflects an obstruction in your airways. While peak flow is less accurate than office spirometry for monitoring of lung function, peak flow monitoring at home can help you manage your symptoms at home and help indicate when an asthma attack may be approaching.

For more information, see WebMD’s Using a Peak Flow Meter.

Chest X-Ray -- while not routinely required, if there are symptoms that may be caused by another condition such as pneumonia, your doctor may want to do a chest X-ray. Or, if your asthma treatment is not working as well as it should, a chest X-ray may help to clarify the problem.

For more information, see WebMD's Asthma Tests.

Diagnosing Asthma Accurately

In diagnosing asthma, your doctor may order other asthma tests, including a methacholine challenge test. Methacholine is an agent that, when inhaled, causes airways to spasm and narrow if asthma is present. For more information, see WebMD's Pulmonary Function Tests.

Not everyone needs every asthma test. Trust your doctor to decide which set of asthma tests is best in your case to ensure no other medical problems are present. This can help you avoid extra testing that may add little to your diagnosis and only increases the number of tests and expense. If you still do not feel comfortable with the asthma diagnosis, talk to your doctor to see if more testing is necessary. Or, get a second opinion until you have peace of mind that the asthma or breathing problem has been diagnosed correctly. Then, proper asthma treatments can begin.

Getting back in control of your asthma depends on an accurate asthma diagnosis and asthma support. Once asthma is properly diagnosed, your doctor can prescribe the most effective asthma treatments, including an asthma inhaler and inhaled steroids that can relieve your breathing problems and help with prevention of asthma symptoms.

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