The pharmacokinetics of theopec (TP) and theobiolong (TB) was studied and compared to theotard and durophylline in 24 bronchial asthma patients. The efficacy of the continuous use of TP and TB was examined in 64 patients. Theophylline (TPh) was absorbed from TP tablets according to the laws of the kinetics of the first order, i. e. one-third of the dose was absorbed rapidly whereas the remaining two-thirds 7.5 times were slowly. The kinetics of TPh absorption from TW was marked by the zero order at a constant rate of 45 mg/h. The volume of distribution, the elimination rate constant, the total clearance, and bioavailability of the drugs under comparison did not differ significantly. During continuous treatment with TP and TB, equiponderant concentrations of TPh were attained by the 4th day, the mean maximum concentration of TPh for TP was 10.6 +/- 1.8, that for TB 9.6 +/- 0.9 micrograms/ml. By the 7th day of the treatment with TP and TB a beneficial clinical effect was reached in 79 and 81% of the patients, respectively, in spite of the fact that there was no well-defined correlation with the changes in the volume of forced expiration per second. During TP and TB intake, the side effects common to TPh occurred equally often (in 19 and 23% of cases, respectively), but they were short-lived and disappeared by themselves or after correction of the dosage. As for TP, the side effects were mostly recorded on the part of the gastrointestinal tract whereas TB provoked tachycardia, cardialgia which should be taken into account in cases where the drug is prescribed to patients with concomitant diseases.
Adult Asthma