Pharmacokinetics and pharmacodynamics of a short- and long-acting theophylline medication (Theolair and Theolair retard) in normals and asthmatics. Part II: Lung function and side effects.

Six normals and six patients with chronic obstructive lung disease were treated with a short- and long-acting theophylline (Theolair and Theolair retard). During treatment the lung function data of the patients showed an improvement on day 1, but no further improvement on days 4 and 7, despite the higher theophylline plasma concentration on these last days. There was no close correlation between the improvement of lung function and the theophylline plasma concentration, nor was there any difference between Theolair and Theolair retard as regards improvement of lung function. Side effects were negligible, and the theophylline plasma concentration was rather low. It seems advisable to use a higher dosage of the theophyllines and perhaps it is even better to combine them with other bronchodilators.