Ashwin Kumar

ASTHMA:
Asthma is defined simply as reversible airway obstruction. Asthma is a chronic condition involving the respiratory system in which the airway occasionally constricts, becomes inflamed, and is lined with excessive amounts of mucus.The airway constriction responds to bronchodilators.
CAUSES:
These episodes may be triggered by such things as exposure to an environmental stimulant (or allergen) such as cold air, warm air, perfume,[3] moist air, exercise or exertion, or emotional stress. In children, the most common triggers are viral illnesses such as those that cause the common cold.The hygiene hypothesis is a theory about the cause of asthma and other allergic disease, and is supported by epidemiologic data for asthma.
SIGNS AND SYMPTOMS:
This airway narrowing causes symptoms such as wheezing, shortness of breath, chest tightness, and coughing. The airway constriction responds to bronchodilators. Between episodes, most patients feel well but can have mild symptoms and they may remain short of breath after exercise for longer periods of time than the unaffected individual.
During very severe attacks, an asthma sufferer can turn blue from lack of oxygen, and can experience chest pain or even loss of consciousness. Just before loss of consciousness, there is a chance that the patient will feel numbness in the limbs and palms may start to sweat.