Terbutaline sustained-release tablets in nocturnal asthma--a placebo-controlled comparison between a high and a low evening dose.

The effects of oral treatment with terbutaline sustained-release (SR) tablets (Bricanyl Depot) were studied in nine patients who had bronchial asthma and marked diurnal variation in ventilatory function. In a randomized and double-blind study, the patients were treated with terbutaline SR 7.5 mg b.i.d., terbutaline SR 7.5 mg in the morning and 15 mg in the evening and terbutaline SR placebo b.i.d. Each treatment was given for 1 week. The nocturnal decline in the peak expiratory flow rate (PEFR) was 45% during the placebo period, 27% after the lower and 22% after the higher terbutaline SR evening dose (P less than 0.01 for both treatments compared to placebo). The mean morning PEFR was significantly higher with the high evening dose than with the low evening dose (P less than 0.01). Mild to moderate side effects were noted. The sustained-release preparation of terbutaline seems to be of clinical value in preventing or relieving nocturnal asthma and early morning dipping. The flexible dose technique, with a higher evening dose, results in further improvements in these patients.