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When asthma acts up

Learn what happens during an asthma flare-up and when to call for help.

When your asthma flares up, it can make the simple act of breathing difficult.

Asthma flare-ups, also called asthma episodes or attacks, can happen when factors such as allergies, cigarette smoke or cold air make your asthma symptoms worse.

Anatomy of a flare-up

The air you breathe travels to and from the lungs through airway tubes called bronchi and smaller tubes called bronchioles. In people with asthma, these airways are often swollen and sensitive, according to the National Heart, Lung, and Blood Institute (NHLBI). During an asthma attack, inflammation increases as the airways overreact to irritants or other triggers.

Here's what happens:

  • Inside your lungs, the airways begin to narrow as their muscular walls contract and tissue inside them swells. This restricts the flow of air.
  • Cells inside the airways start to make more mucus, a thick substance that further restricts air flow.

Symptoms of a flare-up

The symptoms of an asthma attack may develop suddenly or gradually. The NHLBI and the American Academy of Family Physicians list these symptoms of a flare-up:

  • Coughing.
  • Wheezing, especially when you breathe out.
  • Chest tightness.
  • Trouble breathing.
  • Coughing up mucus.

If you don't have asthma, you can get an idea of what an attack feels like by jogging in place for a few minutes and then breathing through a straw while pinching your nose.

When to call for help

Most asthma attacks are moderate or mild, and taking medicines will relieve symptoms within a few minutes.

But sometimes the symptoms get worse instead of better and lead to a severe asthma attack. This is a medical emergency that requires rapid attention, the American Lung Association and the Asthma and Allergy Foundation of America caution.

Symptoms of a severe attack may include:

  • Trouble talking as breathing becomes more difficult.
  • A grayish or bluish color in the face, lips and fingernails.
  • "Sucked-in" skin around the ribs.
  • Symptoms that aren't helped by using your asthma medications.
  • An expanded chest that won't deflate when you exhale.
  • Rapidly moving nostrils.

Make prevention a priority

Asthma can't be cured, but proper treatment can usually keep symptoms in check and allow people to live actively without having asthma attacks. If you have asthma, follow your treatment plan closely and ask your doctor how to avoid situations and factors that could trigger an asthma attack.

Reviewed 10/2/2022

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