What is severe asthma?

Let’s start with one potential cause: eosinophils

Eosinophil graphic

To understand possible causes of severe asthma attacks, it’s important to understand the role eosinophils (ee-uh-sin-uh-fils) can play.


Eosinophils are normal white blood cells in your body. If you have severe asthma, you may have increased levels of eosinophils, which can worsen inflammation in your lungs. Inflammation can cause severe asthma attacks.


Your doctor can give you a simple blood test that measures eosinophil levels to help determine if you have severe eosinophilic asthma.

Once you have a severe eosinophilic asthma diagnosis, together, you and your doctor will decide if adding a different kind of asthma treatment, like NUCALA, could help. Curious? Take a deeper look at how NUCALA works.

Could you have severe asthma?


If you’re taking all your asthma medications

Asthma controller medicines, including high-dose inhaled corticosteroid.

but still struggling, it could be severe asthma. These are some of the key signs doctors look for when diagnosing severe asthma.
Poor Symptom Control

Poor symptom control

Are you coughing, wheezing, having difficulty breathing, frequently using a rescue inhaler, or waking up at night?

Worsening Asthma

Worsening asthma

Having flare-ups? These are also called exacerbations or severe asthma attacks—when symptoms don’t improve and you need to add oral steroids.

ER Visits or Hospitalizations

ER visits or hospitalizations

Is the severity of your asthma attacks sending you to the ER or requiring hospitalization?

If this sounds familiar, it’s time to talk to your doctor about your current asthma treatments.

Severe Asthma Facts
Break the asthma cycle

Repeated asthma attacks and inflammation caused by long-term, uncontrolled asthma can lead to more asthma attacks or exacerbations.

Let’s prep for next steps with your doctor

Did you know most severe asthma can be controlled? To get the right diagnosis, it’s important to be open and honest with your doctor. Use these points to help get the conversation started:

  1. Start by telling your doctor about your asthma management plan.
  2. Tell your doctor when your symptoms get worse. Your symptoms may require you to see a specialist.
  3. Is your asthma interfering with your daily activities? Tell your doctor about your symptoms and how they affect your life.
  4. Ask for a blood test to see if you have severe eosinophilic asthma and if NUCALA may be right for you.
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So, why NUCALA?

If you’re ready for a different kind of treatment for your severe asthma, see what NUCALA can do for you.

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