Asthma is a chronic respiratory condition that causes inflammation and narrowing of the airways, leading to difficulty breathing. Symptoms can vary in intensity and may include: wheezing, shortness of breath, chest tightness, coughing (especially at night or early morning). Common triggers include allergens (pollen, dust mites, pet dander), respiratory infections (cold, flu), physical activity (exercise-induced asthma), weather changes (cold air, humidity), smoke, strong odors, pollution. Diagnosis is established by clinical history, physical exam, spirometry (pulmonary function tests), allergy testing if indicated. Management includes rescue inhalers during attacks, long-term control medications (inhaled corticosteroids, long-acting bronchodilators), leukotriene inhibitors (Singulair). Asthma often starts during childhood, symptoms may improve or go in remission over time but it is a lifelong disease.