What Is Brittle Asthma?

Medically Reviewed by Carol DerSarkissian, MD on August 30, 2022
3 min read

Asthma is a condition that makes it hard to get air in and out of your lungs. The airways in your lungs swell and cause shortness of breath that can make you wheeze and cough.

Brittle asthma is a rare and serious form of asthma. It can cause attacks so severe that you have to go to the hospital to get your symptoms under control. Doctors aren’t sure what causes it, but it can be triggered by animals, dust mites, certain types of fungus, or some foods.

The percentage of people with asthma who have brittle asthma is well below 1%.

There are two types of this kind of severe asthma.

Type 1: This causes trouble breathing throughout the day, even if you take high doses of asthma drugs. It affects your peak flow -- how well you can push air out of your lungs in a single, forceful breath. For people with this type, their peak flow is well out of the normal range most of the time.

Type 2: This causes sudden severe asthma attacks that happen for no apparent reason, even if your breathing had been under control. The attacks can be so serious that they’re life-threatening.

Type 1 is more likely to affect women and tends to show up between the ages of 15 and 55. Type 2 affects men and women equally.

For most people with brittle asthma, symptoms happen after they’re exposed to certain things.

With type 1, this is often dust mites, certain food, or animals, especially dogs, cats, and horses. The most common food triggers include bread, pasta, crackers, potatoes, citrus fruits, eggs, fish, soybeans, peanuts, yeast, and dairy foods like milk and cheese.

People with type 2 tend to react mainly to certain kinds of fungal spores.

A doctor will use the following to figure out if you have brittle asthma:

  • Your symptoms
  • Your triggers and how they affect you
  • Your personal and family medical history
  • How well you can breathe
  • Your peak flow

Type 1 is treated with high doses of steroids, breathed in through an inhaler or taken as pills. It’s also treated with drugs called bronchodilators that open the airways in your lungs.

Depending on your triggers, certain diet changes may help ease type 1 symptoms, too. Because it can be hard to get enough nutrients if your diet is limited, your doctor may recommend supplements to make sure you get vitamins A, C, and B, plus magnesium and selenium.

People who have type 1 sometimes have an attack that their medicines can’t control. When that happens, you need medical help right away. Treatment at a hospital may include high doses of steroids and bronchodilators called beta2-agonists.

Treatment of type 1 brittle asthma is an ongoing process, and it can take a lot of trial and error to find what works for you. You’ll probably see small improvements over time rather than major breakthroughs.

People with type 2 often need to stay in the hospital to get the symptoms of an attack under control. It’s also treated with medicines to open the airways in your lungs. You may need to take the medicine through a nebulizer -- a machine that lets you breathe in mist that has the drug in it. If the attack is very serious, you may need a breathing machine, called a ventilator, to help control it.

With type 2, the best way to avoid an attack is to understand your triggers and stay away from them. It also can be a good idea to have syringes with the drug epinephrine (adrenaline) on hand. It works very quickly and can reopen your airways within minutes.