[Comparison of two long-acting theophylline preparations in daily evening administration]

The therapeutic value of a sustained-release theophylline preparation (Theospirex retard 300 mg) with administration of the daily dose once a day in the evening compared to the 2 x 1 dosage usual was investigated in 19 patients suffering from asthma symptoms manifested mainly at night. In this open randomized clinical trial, a sustained-release theophylline preparation (400 mg) which had already been used for administration once a day in the evening served as reference preparation. The single dose in the evening for both preparations was 600 mg pure theophylline. Target parameters were the level of theophylline in the blood, the pulmonary function, symptoms of asthma, and the tolerance of the two sustained-release drugs. The theophylline serum levels after 13 respectively 22 hours were 12.44 and 6.98 micrograms/ml for the reference drug and 11.72 and 7.11 micrograms/ml for Theospirex retard. Equivalence of the two drugs was shown in the parameters pulmonary function, symptoms of asthma and tolerance. This study shows that 300 mg Theospirex retard film-coated tablets are suitable for a single administration of the entire daily dose in the evening.