Symbicort (Budesonide/Formoterol) is use to treatment of asthma and COPD exacerbations. Budesonide is a glucocorticosteroid with anti-inflammatory effect. Improvement in asthma control can occur within 24 hours with maximum clinical benefit usually achieved within 1 to 2 weeks. Formoterol is a selective beta2-adrenergic agonist that induces relaxation of bronchial smooth muscle. The bronchodilating effect sets in rapidly, within 1-3 minutes after inhalation and has a duration of 12 hours after a single dose.