Chronic asthma is often diagnosed when patients complain of difficult breathing while doing least exertion. Patients complain of difficult breathing while doing exertion. Patient often cough up thick mucus and their skin may have a bluish tinge caused by lack of oxygen in the blood. If patient develops severe dyspnoea or swelling of the legs or ankles they require immediate attention as symptoms are leading to congestive heart failure. Tobacco smoking, long term exposure to tobacco smoke, repeated respiratory infections, industrial exposures in toxic fumes or dust are also the known causes of chronic asthma. It may lead to the symptoms of mucus cough, shortness of breath, wheezing, fatigue and headache.