Other tests, such as a chest x-ray or an electrocardiogram, may be needed to find out if a foreign object, or other lung diseases or heart disease could be causing asthma symptoms.

A correct diagnosis is important because asthma is treated differently from other diseases with similar symptoms.

Depending on the results of your physical exam, medical history, and lung function tests, your doctor can determine how severe your asthma is. This is important because your asthma severity will determine how your asthma should be treated, and what the options are for treatment.

A general way to classify severity is to consider how often a person has symptoms when that person is not taking any medicine or when their asthma is not well controlled.

Based on symptoms, the four levels of asthma severity classification are:

Mild Intermittent: occurs when your asthma is not well controlled, you have asthma symptoms twice a week or less, and you are bothered by symptoms at night twice a month or less.

Mild Persistent Asthma: occurs when your asthma is not well controlled, you have asthma symptoms more than twice a week, but no more than once in a single day. You are bothered by symptoms at night more than twice a month. You may have asthma attacks that affect your activity.

Moderate Persistent Asthma: when your asthma is not well controlled, you have asthma symptoms every day, and you are bothered by night=time symptoms more than once a week. Asthma attacks may affect your activity.

Severe Persistent Asthma: when your asthma is not well controlled, you have symptoms throughout the day on most days, and you are bothered by night-time symptoms often. In severe asthma, your physical activity is likely to be limited.

Anyone with asthma can have a severe attack-even those who have intermittent or mild persistent asthma.

Your doctor should provide most of the following information to you (and if they don't then ask them to provide it):

How to take your long-term daily medication correctly
What things tend to make your asthma worse and ways to avoid them
Early signs to watch for that mean your asthma is starting to get worse (like a drop in your peak flow number or an increase in symptoms)
How and when to use your peak flow meter
What medication and how much to take to stop an asthma attack and how to use it correctly
When to call or see your doctor
When you should get emergency treatment

This information will help you successfully manage asthma, so that you can lead a normal life.