Effect of prednisolone on theophylline pharmacokinetics in patients with chronic airflow obstruction

The effect of prednisolone on the elimination kinetics of theophylline was studied in a group of nine patients with chronic airflow obstruction. Volume of distribution, plasma half life, and clearance after a single intravenous dose of aminophylline (5.6 mg/kg) were unchanged by prednisolone treatment (20 mg daily for three weeks). The metabolism of an intravenous bolus of theophylline is not influenced by oral prednisolone.