Nifedipine in bronchial asthma.

In 11 patients with bronchial asthma and regular overnight falls in PEFR of greater than 15%, we demonstrated significant bronchodilation restricted only to large airways after the administration of a single dose of 10 mg of nifedipine. A statistically significant increase in PEFR, SGaw, and FEV1 was noticed at 1 and especially 2 hr after nifedipine administration. During 4 days of nifedipine treatment (10 mg t.i.d.), the overnight fall in mean PEFR was statistically significant (p less than 0.02) and less than the mean fall of PEFR during the 4 days of placebo treatment. Thus nifedipine does modify the basal bronchial tone of patients with asthma and diminishes the circadian swing of airway resistance.