When asthma symptoms appear and are diagnosed in adults older than 20, it is typically known as adult-onset asthma. Adult-onset asthma is more common in women than in men and is possibly related to allergies or allergic asthma. About half of adults who have asthma also have allergies. At other times, adult-onset asthma may be the result of commonplace substances in work (called occupational asthma) or home environments, and the asthma symptoms come on suddenly.

What is asthma?

Asthma is a disorder of the lungs that causes the airways to:

• Swell (or become inflamed), specifically in the airway linings



• Produce large amounts of mucus that is thicker than normal



• Become more narrow because of muscle contractions surrounding the airways

The symptoms of asthma include:

• Feeling short of breath



• Frequent coughing, especially at night



• Wheezing (a whistling noise during breathing)



• Difficulty breathing

What is adult-onset asthma?

When a doctor makes a diagnosis of asthma in people older than 20, it is known as adult-onset asthma.

Among those who may be more likely to get adult-onset asthma are:

• Women who are having hormonal changes, such as those who are pregnant or who are experiencing menopause



• Women who take estrogen following menopause for 10 years or longer



• People who have just had certain viruses or illnesses, such as a cold or flu



• Obese people



• People with allergies, especially to cats



• People who are exposed to environmental irritants, such as tobacco smoke, mold, dust, feather beds, or perfume. Irritants that bring on asthma symptoms are called "asthma triggers." Asthma brought on by workplace triggers is called "occupational asthma."