[Interactions of theophylline and nifedipine]

We analyzed theophylline serum levels in steady state of 10 subjects (out of them 7 patients with chronic obstructive lung disease (COLD) and 3 volunteers). Serum theophylline concentrations were measured after oral application of 3 X 280 mg theophylline (Theophyllin retard 280 mg) and in a second condition after accessory administration of 3 X 20 mg nifedipine (Corinfar). No significant difference was found concerning theophylline levels before and after nifedipine application. The ventilation parameters FVC (forced vital capacity) and FEV1 (forced expiratory volume in one second) were not altered during nifedipine dosing. The results are discussed in comparison with data of literature.