Pulmonary System

An increase in FEV1 of at least 12% (and ≥200 mL in adults) after a bronchodilator, with a low FEV1/FVC ratio that improves. Reversibility distinguishes asthma from fixed COPD obstruction.

Episodic wheeze, cough (often nocturnal), chest tightness, and dyspnea, triggered by allergens, exercise, cold air, viral URIs, or irritants. Symptoms are intermittent and reversible.

An inhaled corticosteroid (ICS) is the foundation of controller therapy. For moderate-to-severe disease, low-dose ICS-formoterol can serve as both maintenance and reliever (MART/SMART). Step up to ICS-LABA as needed.

A short-acting beta-2 agonist (SABA) such as albuterol provides rapid bronchodilation. GINA now also endorses as-needed low-dose ICS-formoterol as reliever therapy.

Oxygen to keep SpO2 ≥92–94%, repeated/continuous inhaled SABA (often with ipratropium), and systemic corticosteroids (oral prednisone or IV methylprednisolone). Add magnesium sulfate for severe cases.

A LABA must always be combined with an ICS in asthma. LABA monotherapy increases asthma-related death because it masks airway inflammation without treating it.