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Asthma Classification

Based on the results of your visit with an asthma specialist, your asthma will be classified in one of the following categories (based on National Heart Blood and Lung Institute guidelines):

Mild Intermittent Asthma

• Symptoms of cough, wheeze, chest tightness or difficulty breathing less than twice a week
• Flare-ups-brief, but intensity may vary
• Nighttime symptoms less than twice a month
• No symptoms between flare-ups
• Lung function test FEV1 equal to or above 80 percent of normal values
• Peak flow less than 20 percent variability AM-to-AM or AM-to-PM, day-to-day.

Mild Persistent Asthma

• Symptoms of cough, wheeze, chest tightness or difficulty breathing three to six times a week
• Flare-ups-may affect activity level
• Nighttime symptoms three to four times a month
• Lung function test FEV1 equal to or above 80 percent of normal values
• Peak flow less than 20 to 30 percent variability.

Moderate Persistent Asthma

• Symptoms of cough, wheeze, chest tightness or difficulty breathing daily
• Flare-ups-may affect activity level
• Nighttime symptoms 5 or more times a month
• Lung function test FEV1 above 60 percent but below 80 percent of normal values
• Peak flow more than 30 percent variability.

Severe Persistent Asthma

• Symptoms of cough, wheeze, chest tightness or difficulty breathing continual
• Nighttime symptoms frequently
• Lung function test FEV1 less than or equal to 60 percent of normal values
• Peak flow more than 30 percent variability.

The level of asthma severity will determine what types of medicine you will need to get your asthma under control.

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Last Update: August 1, 2003