asthma
Imagine your airways as soft, springy tubes that should stay comfortably open. In asthma, those tubes have a short fuse: certain triggers make their muscles clamp down, the lining swell, and sticky mucus build up, so air has to squeeze through narrowed passages. The hallmark feeling is a tight chest, a whistling wheeze, cough, and breathlessness that come and go.
Medically, asthma is a chronic inflammatory disease of the airways marked by three linked features: variable, largely reversible airflow obstruction; airway hyperresponsiveness (over-twitchy airways); and ongoing inflammation, often involving eosinophils and allergic pathways. Symptoms typically vary over time and worsen at night or with triggers such as allergens, exercise, cold air, or viral infections.
It is important to be precise: asthma is usually reversible, meaning airflow improves substantially after a bronchodilator or with treatment — a key contrast with COPD, where obstruction is largely fixed. Asthma spans a wide spectrum, from mild and intermittent to severe and life-threatening, and most people achieve good control with inhaled anti-inflammatory therapy plus a reliever. This entry is educational, not a substitute for an individual diagnosis or treatment plan.
A teenager wheezes and coughs whenever she runs in cold weather but breathes normally at rest; spirometry shows airflow that improves markedly after a puff of salbutamol — a classic picture of reversible, hyperresponsive airways.
Exercise- and cold-triggered, reversible airflow obstruction typical of asthma.
A common mistake is treating asthma with reliever inhalers alone. Because the underlying problem is inflammation, regular inhaled corticosteroids — not just bronchodilators — are the foundation of control for most people, even when they feel well.