Asthma is a serious disorder affecting millions of Americans each year. As the summer heats up, the nation’s emergency physicians want those affected by it to know how to prevent a visit to the emergency department.

Asthma is a chronic disease of the airways in your lungs. There are an estimated 25.7 million people with asthma, 7 million of whom are children.

According to the Centers for Disease Control and Prevention, asthma prevalence has increased from 7.3 percent in 2001 to 8.4 percent in 2010. It can never be cured, but with the right treatment it can be kept under control.

In many cases, asthma symptoms can be brought on by allergy-causing substances, including: animal, mold, pollen, dust, smoke, chemicals in air/food, stress, respiratory infections (common cold, flu, bronchitis), changes in air and exercise.

Symptoms include shortness of breath that get worse with exercise or activity, coughing or wheezing without producing phlegm. Asthma sufferers should go to the nearest emergency department if they experience:

Abnormal breathing pattern, rapid pulse, extreme difficulty breathing, bluish lips and face, extreme sweating, severe anxiety due to shortness of breath, chest pain and tightness in the chest.