Recommended standard theophylline doses are inadequate in chronic obstructive pulmonary disease

Theophylline serum levels were measured in 34 adult patients suffering from chronic obstructive pulmonary disease. It was not possible to establish a simple relationship between the dose of theophylline and the serum levels measured. Only 53% of peak concentrations and 40% of trough concentrations were found to be within the recommended therapeutic range. In 82% of patients studied, two or more drugs in addition to theophylline, were required for adequate bronchodilation. For optimisation of theophylline therapy, the importance of measuring serum theophylline levels is stressed.