Bronchodilator therapy for chronic obstructive pulmonary disease.

Chronic obstructive pulmonary disease (COPD) is a heterogeneous group of diseases characterized by cough, sputum production, dyspnoea, airflow limitation and bronchial hyperreactivity. The airflow limitation declines progressively and is irreversible or partially reversible. Bronchodilator therapy is prescribed to relieve the symptoms, reverse airway obstruction and hopefully slow the rate of disease progression and decelerate the decline in pulmonary function. During acute exacerbation, inhalation of beta2-agonists remain the therapy of choice. The usefulness of anticholinergic inhalation in acute attacks is investigated in order to determine if a higher dose and more frequent administration have same benefit as beta2-agonists inhalation. Theophylline is usually given orally as a sustained release formulation for chronic maintenance therapy. Some patients may benefit from theophylline infusion during an acute phase when appropriately used; however, sympathomimetic agents fail to produce adequate bronchodilation. During interim periods of stability, inhalation of ipratropium bromide has increased in popularity as a regular long-term bronchodilator therapy. Although ipratropium and beta2-agonists are equally efficacious when the dosage is adequate enough, a combination of both provides a rapid onset of action of the adrenergic agents and a prolonged action of the anticholinergic. Furthermore, this combination can be given in a reduced dose, thereby avoiding side-effects. Inhalation techniques can influence the efficacy of bronchodilator therapy. For severe dyspnoeic patients or patients with poor technique of co-ordination with metered-dose inhaler (MDI), attachment of a spacer to the MDI or using a nebulizer will overcome these difficulties. Bronchodilator therapy can not prevent the development of COPD or slow down the decline of pulmonary function, other interventions should be included in a comprehensive management programme.