In asthma, airways to the lungs become blocked, causing many symptoms that result in difficulty in breathing. Asthma can be allergy related, caused by allergens such as pet dander, mold or pollen. It can also develop from outside factors such as stress, cold air or cigarette smoke. According to the Asthma and Allergy Foundation of America, whether severe asthma is allergy or non-allergy related, the symptoms are often the same. As the asthma becomes more severe, symptoms worsen and occur more frequently.
Wheezing
One of the first signs of severe asthma is wheezing. Although this is also a symptom of early asthma, as the disease progresses, the wheezing worsens. The Mayo Clinic reports that the wheezing sound often happens upon exhaling. This is often due to the fact that airways are constricted, and air is being forced through them.
Difficulty Breathing
Constricted airways make it extremely difficult for air to flow freely into the lungs, making breathing difficult and labored. The Cleveland Clinic notes that with severe asthma, you're not completely able to expel all of the air from the lungs, breaths become rapid, and there's a feeling of not being able to catch your breath. Occasionally, the inability to breathe well results in pale and sweaty facial features, and a bluish color in the fingers or lips. When these symptoms occur, it can be life-threatening, and medical attention should be sought immediately.
Chest Pain
According to the National Institutes of Health, in its severe state, asthma can cause chest pain. This can be from the lack of oxygen due to difficulty in breathing, and the anxiety and stress the symptoms can cause. An increase in the pulse rate can also stem from the anxiety a person feels as a result of experiencing severe asthma symptoms.
Cough
A symptom of severe asthma that also occurs in its early stages is a cough. The NIH reports that the cough may or may not be accompanied by sputum or phlegm. As asthma becomes more severe, what once may have been an occasional cough becomes more persistent and feels as if it won't stop.


