COPD actually comprises several different types of lung diseases. Each type is identified by “stage” based on severity of symptoms. Your doctor will determine which stage you are in, and thus your best treatment.
Stage 1, Mild. Symptoms in this stage include minor airflow limitation, coughing, and buildup of mucus.
Stage 2, Moderate. At this stage, airflow limitation increases and coughing worsens. Doctors measure your ability to inhale adequately using a spirometry test, and may prescribe an inhaler or other type of COPD medication.
Stage 3, Severe. People in Stage 3 COPD often feel tired. Their symptoms have worsened and breathing is more difficult. At this stage, a doctor may prescribe an inhaler or steroid treatment.
Stage 4, Very Severe. At this stage breathing has become extremely difficult. In some cases, complications with breathing can be life-threatening.The lack of airflow that defines very severe COPD can affect the heart and circulatory system, and oxygen therapy or surgery may be prescribed.