Severe asthma refers to asthma that does not respond well to regular asthma treatments, such as inhaled corticosteroids and inhaled bronchodilator medications.

More than 26 million people in the United States have asthma. Severe asthma is relatively uncommon, generally affecting 5–10% of people with asthma.

Those with severe asthma usually find their symptoms difficult to control, which means that asthma attacks are more dangerous. By working with a doctor, a person with severe asthma can find ways to manage their symptoms.

Beyond taking medications, it is important to learn to identify and avoid triggers and prevent and manage asthma attacks.

In this article, we look at the causes, symptoms, and treatments of severe asthma.

What is severe asthma?

Woman with severe asthma using inhaler
Severe asthma can cause persistent symptoms that may be difficult to control.

Doctors categorize asthma severity by how well the symptoms respond to treatment. People with severe asthma find it difficult to control their symptoms using the usual medications.

Severe, persistent asthma involves symptoms that persist throughout the day and night. Asthma may get in the way of daily activities and make it difficult to sleep — nighttime symptoms often arise in people with severe asthma.

When symptoms are harder to control, a person has a greater risk of asthma-related complications.

According to guidelines from the National Institutes of Health (NIH), severe asthma has the following features:

  • symptoms that occur throughout the day
  • being woken up by symptoms, often 7 nights per week (ages 5 and older)
  • for ages 4 and younger, being woken up by symptoms on more than 1 night per week
  • symptoms that require short-acting beta 2-agonist therapy several times per day
  • symptoms that significantly limit a person’s regular activities
  • an FEV 1 measurement of less than 60% of usual (ages 5 and older)

FEV 1 refers to forced expiratory volume. It is a measurement that shows how much air a person can force from their lungs in 1 second. This can give a healthcare provider a better idea about a person’s lung function.

A 2014 article states that a person has severe asthma if the following medications do not control their symptoms:

  • inhaled corticosteroids and extra treatments, including a long-acting inhaled beta 2-agonist, theophylline, or montelukast
  • oral corticosteroid treatment for at least 6 months in a year

Symptoms

Severe asthma can cause chest tightness and pain.
Severe asthma can cause chest tightness and pain.

People with asthma experience the condition differently. For many, symptoms can be unpredictable. This makes it difficult to pinpoint exactly what it is like to have severe asthma. There are, however, typical symptoms and experiences.

Severe asthma can affect a person’s ability to perform usual daily tasks. If a person is not using effective treatment, symptoms can be debilitating.

Sometimes, symptoms can occur throughout the day and during the night, forcing the person to wake up.

Asthma symptoms can range in severity from minor inconveniences to life-threatening attacks, during which symptoms worsen all at once.

Symptoms of asthma include:

Diagnosis

Doctors diagnose severe asthma if regular asthma treatments are unable to control the symptoms well.

This means that it may take some time for a diagnosis — a person may have to try various treatments to see if they work.

Doctors use a three-stage process for diagnosing asthma:

  • asking about a person’s medical history
  • performing a physical exam
  • conducting breathing function tests

They may also test for other conditions that have similar symptoms.

Causes

The medical community has yet to understand the exact cause of asthma, but multiple factors, especially allergies, may play a role.

A 2013 study reports that 75.4% of participants aged 20–40 with asthma also had allergies.

Additional research reveals a link between smoking tobacco and an increased risk of asthma, as well as other respiratory issues. Children who spend time around adults who smoke can experience similar effects.

Also, a variety of environmental factors can contribute to asthma symptoms. Research from 2017 shows that air pollution results in a higher recurrence of asthma and asthma-related hospital admissions.

A 2014 report suggested a link between obesity and asthma. The American Academy of Allergy, Asthma & Immunology noted that, based on other research, «Increased obesity in general has been suggested as a contributing factor for the increase in asthma prevalence.»

Treatment

A person experiencing a severe asthma attack should seek medical attention.
A person experiencing a severe asthma attack should seek immediate medical attention.

The focus of asthma treatment is to control the symptoms. This includes managing the underlying airway inflammation, minimizing the risk of future attacks, and preventing lung damage.

People with severe asthma need to take medications more frequently and in stronger dosages than people with mild asthma. Speak to a doctor to find out the best way to manage specific symptoms.

If a person has a severe asthma attack, they should go to the hospital right away. Asthma attacks can be life-threatening, especially when a person’s asthma does not respond well to treatment.

According to asthma experts, the best way to reduce the risk of severe attacks and uncontrolled symptoms is to avoid triggers as much as possible and to take prescribed treatments.

Quick-relief and long-term treatments are available.

The main quick-relief asthma medications are selective short-acting beta 2-agonists. A person takes this type of medication when asthma symptoms occur.

Examples of this class of drug include:

  • metaproterenol
  • albuterol (Ventolin HFA, ProAir, Proventil)
  • levalbuterol (Xopenex)

For long-term controller therapy, doctors recommend daily drugs to prevent asthma flares. Inhaled corticosteroids are among the most effective long-term asthma medications.

Inhaled corticosteroids can have side effects, including oral thrush, which is a yeast infection that develops in the mouth. A person can protect against thrush by rinsing their mouth after using the inhaler.

Outlook

Asthma is a common condition that affects millions of people every day, and its severity varies.

While most cases of asthma respond well or adequately to treatment, severe asthma does not respond sufficiently to the usual treatment options.

People with severe asthma should do their best to avoid triggers. Also, working with a doctor will help identify the most effective treatments.