A person with asthma has oversensitive airways. During an asthma attack, these passages narrow in response to some form of irritation, making breathing difficult. Something that initiates an asthma attack is known as a trigger. Anyone can get asthma, but it most often occurs in children under age 5 and in adults in their 30s. You are at greater risk of developing asthma if you have allergies or if one of your parents has asthma.
People living in cities also have higher rates of asthma.
During an asthma attack, the airways become swollen and inflamed. The body secretes excess mucous that clogs the breathing passages. The muscles around the airways also tighten, further restricting breathing. Symptoms of an asthma attack include coughing, wheezing, shortness of breath and a tight feeling in the chest. In a severe attack, a person's lips and fingernails may turn a bluish color.