Asthma Disease In 20 Million Americans. Asthma is a chronic disease of the lungs in which the airways become blocked or narrowed causing breathing difficulties. Asthma affects more than 20 million people in the United States and is divided into two types: allergic (extrinsic) asthma and non-allergic (intrinsic) asthma.Allergic (extrinsic) asthma is associated with symptoms that are triggered by an allergic reaction. Allergic asthma is airway obstruction and inflammation that is partially reversible with medication. Allergic asthma is the most common form of asthma. Allergic asthma is triggered by inhaled allergens such as dust mite allergen, pet dander, pollen, mold, etc. resulting in asthma symptoms.
Non-Allergic (intrinsic) asthma is set off by factors not related to allergies. Like allergic asthma, non-allergic asthma is characterized by airway obstruction and inflammation that is at least partially reversible with medication; however symptoms in this type of asthma are NOT associated with an allergic reaction. Non-allergic asthma is triggered by other factors such as anxiety, stress, exercise, cold air, dry air, hyperventilation, smoke, viruses or other irritants. In non-allergic asthma, the immune system is not involved in the reaction.
Many of the symptoms of allergic and non-allergic asthma are the same: coughing, wheezing, shortness of breath or rapid breathing, and chest tightness).
On July 14, 2005, the FDA cleared asthma drugs Advair and Serevent, allowing them to stay on the market as long as warning labels clearly alert patients to potential risks. Made by GlaxoSmithKline, the medications contain salmeterol, a bronchodilator known as a beta2-against.
It works by relaxing the bronchial muscles, thereby improving air flow for many of the 15 million asthma sufferers in the U.S. Regulators became alarmed when Glaxo reported that it had to stop tests of the drug when about 50 out of 26,000 patients being studied suffered more severe asthma attacks.
A few died. After a review by its panel of experts, the FDA voted 12-0 to keep the drugs on the market while adding a “black box” warning, the most extreme warning that can be put on drugs.