Theophylline in asthma and COPD: changing perspectives and controversies.

Theophylline's role in the treatment of airway obstruction has been challenged, yet it remains a useful agent in the management of obstructive lung disease. It has a narrow therapeutic range and frequent side effects. Drug interactions are common, and variations in theophylline clearance among patients arise from individual differences in its absorption, metabolism, and elimination. Acute bronchospasm is best treated with inhaled sympathomimetic agents, but the nonbronchodilator effects of theophylline offer therapeutic benefits for the patient with non-reversible disease. When properly monitored by serum level determinations, theophylline may be used as an adjunct to aerosol therapy and corticosteroids in asthma. However, the patient with COPD may benefit the most from an empiric trial of the drug, using lower doses than were commonly employed in the past.