Asthma is a chronic disease of the lungs in which the breathing airways become inflamed, blocked, and narrowed. Symptoms of asthma include coughing, wheezing, shortness of breath, and chest tightness.

Asthma affects more than 25 million Americans — about 1 in every 12 adults and 1 in 10 children in the United States as of 2009. That number is expected to grow.

Asthma is sometimes classified in two types:

  • intrinsic (also called nonallergic asthma)
  • extrinsic (also called allergic asthma)

If you or your child has intrinsic asthma, the first step to knowing how to avoid triggering an asthma attack is to understand the differences between intrinsic and extrinsic asthma.

Extrinsic asthma is more common than intrinsic asthma.

Intrinsic asthma tends to start later in life, is more common in females, and is typically more severe.

The main difference between the two is the level of involvement of the immune system:

  • In extrinsic asthma, symptoms are triggered by an allergen (such as dust mites, pet dander, pollen, or mold). The immune system overreacts, producing too much of a substance (called IgE) throughout the body. It’s the IgE that triggers an extrinsic asthma attack.
  • In intrinsic asthma, IgE is usually only involved locally, within the airway passages.

Despite these factors, experts generally agree that there are more similarities than differences between extrinsic and intrinsic asthma.

An asthma attack (also called an asthma flare-up or asthma episode) can happen at any time. An attack may last only a few moments, but more severe asthma episodes can last for days.

During an asthma attack, the airways become inflamed, narrowed, and filled with mucus, making breathing more difficult.

The symptoms of intrinsic asthma are essentially the same as those of extrinsic asthma. Symptoms include:

  • coughing
  • wheezing or whistling sounds when breathing
  • shortness of breath
  • chest tightness
  • chest pain
  • rapid breathing
  • mucus in the airways

The exact cause of intrinsic asthma isn’t fully understood.

Experts believe that a combination of genetic and environmental factors play a role in the development of asthma. Researchers now think that the cause of intrinsic asthma is more similar to the cause of extrinsic asthma than previously believed, but more research is needed.

During an attack of asthma, the muscles in the airways thicken and the membranes lining the airways become inflamed and swollen and produce a thick mucus. The airways become more and more narrow, resulting in an asthma attack.

Unlike extrinsic asthma, which is triggered by commonly known allergens, intrinsic asthma may be triggered by a wide range of nonallergy related factors.

Some of the triggers of an intrinsic asthma attack include:

  • stress
  • anxiety
  • changes in weather
  • cold air
  • dry air
  • cigarette smoke
  • fireplace or wood smoke
  • viruses, especially respiratory infections like the common cold
  • air pollution or poor air quality
  • chemicals and fragrances
  • strenuous exercise (triggers what’s also known as exercise-induced asthma)
  • certain drugs, like acetylsalicylic acid (aspirin) and other nonsteroidal anti-inflammatory drugs (NSAIDs), like ibuprofen (Motrin, Aleve)
  • hormone fluctuations
  • acid reflux

Figuring out your triggers can be a little more difficult with intrinsic than with extrinsic asthma. There often aren’t any specific tests that can help you find out what might trigger an attack of intrinsic asthma.

Keeping a journal of symptoms and things you think may have triggered an asthma episode (after one has taken place) can help you determine your unique triggers.

There is no cure for intrinsic asthma, but it can be controlled with asthma medications and by doing your best to avoid triggers.


Unlike people with extrinsic asthma, those with intrinsic asthma usually have a negative allergy skin test, so they often won’t benefit from allergy shots or allergy medications.

Medications for intrinsic asthma are used both to prevent an attack before it starts and to treat an attack that has already started. Your doctor will prescribe the medication that’s best for your particular case. They’ll also help you weigh the pros and cons of each treatment option.

There are two main groups of medications used to treat intrinsic asthma:

Make sure you follow the directions for each type of medication very carefully.

Avoiding triggers

The Centers for Disease Control (CDC) found that, in 2008, nearly half of those with asthma weren’t taught how to properly avoid triggers.

If you have intrinsic asthma, keeping a diary of the events and conditions that preceded an asthma attack can help, but it will take a bit of detective work, time, and patience.

Once you learn what types of situations or products typically trigger your attacks, you can try to create a plan to avoid them. In general, people with intrinsic asthma should try to avoid:

  • catching a respiratory infection by washing your hands frequently and staying away from people who are sick
  • extreme exercise
  • irritants in the environment (like smoke, air pollution, smog, wood fires, and particles in the air)
  • very emotional or stressful situations
  • strong-smelling perfumes, vapors, or cleaning products

Getting yearly flu vaccines along with scheduled vaccinations for whooping cough and pneumonia are also important.

Some triggers, like hormonal changes that occur during the menstrual cycle, are difficult to avoid.

Fortunately, nowadays most people who have asthma are better equipped to handle unavoidable triggers if using medication consistently and correctly.

Breathing exercises

Special deep-breathing exercises can help people with asthma. A regular yoga practice or tai chi, for example, can help you gain control over your breathing and may improve your symptoms and quality of life.

If you have intrinsic asthma, it’s important to be consistent with your medication and to stay vigilant about avoiding your unique triggers. You need a high degree of awareness when it comes to figuring out what triggers your intrinsic asthma attacks.

Asthma attacks can lead to hospitalization if symptoms become severe. They can become life-threatening if not well-controlled. In fact, asthma is responsible for roughly 1.8 million emergency department visits each year. Staying on track with your medication can prevent you from having complications.

Living with intrinsic asthma can be frustrating, but with modern medications and some lifestyle modifications, it’s entirely possible to live a normal life.