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Asthma Health Center

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Asthma Action Plan: Red Zone - Topic Overview

An asthma action plan is based on zones defined by your symptoms, your peak flow, or both. It tells you what to do if you have a sudden increase in your asthma symptoms (asthma attack).

You are in the red zone of your asthma action plan if you have severe asthma symptoms. Symptoms include:

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  • Any shortness of breath while walking, talking, or at rest.
  • Use of the chest muscles to breathe. The skin between, above, and under the ribs collapses inward with each breath (retractions).
  • Wheezing. But if symptoms are very severe, you may not hear any wheezing. Wheezing will stop when the amount of air moving through the bronchial tubes becomes dangerously low. In this case, no wheezing is actually worse than hearing wheezing.
  • Peak expiratory flow less than 50% of your personal best peak flow measurement. To find 50% of your personal best, multiply your personal best measurement by 0.50. For example, if your personal best flow is 400, then 50% of that is 400 times 0.50, which is 200. In this example, a peak expiratory flow less than 200 means you are in the red zone.

Treatment for asthma attacks in the red zone includes:

  • Seeking immediate medical attention while you are following your asthma action plan.
  • Using medicine based on your asthma action plan.
  • Talking with a doctor immediately about what to do next.

    WebMD Medical Reference from Healthwise

    Last Updated: /2, 14 1
    This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.
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