NAB 365 (clenbuterol) and salbutamol in asthmatics: a double-blind clinical trial.

A double-blind comparison between orally administered NAB 365 (clenbuterol) and salbutamol was conducted in 30 impatients with either asthma or chronic bronchitis with asthma who had at least 15% reversibility in airway obstruction following inhalation of 1,500 microgram of orciprenaline. NAB 365 (clenbuterol) was administered to 15 patients at 30 microgram b.i.d. for 3 days; then the dosage was reduced to 20 microgram b.i.d. Salbutamol was administered to the other 15 patients at 4 mg t.i.d. Both drugs were administered for an average of 13 days. NAB 365 (clenbuterol) was shown to be an effective bronchodilator, with more rapid activity than that of salbutamol, on the FVC, FEV1, PEFR, the differences being significant on the third and seventh day of treatment. These findings are briefly discussed. No significant cardiovascular effects were noted for either drug, nor were differences found in need for additional treatment or in side-effects.