Betamethasone valerate compared by the oral and inhaled routes in childhood asthma.

The value of betamethasone valerate by inhalation in the prophylactic therapy of severe childhood asthma has been established. To determine whether the efficacy of this drug is due to a local or a systemic action a double-blind crossover study of 28 days' treatment with oral betamethasone valerate and 28 days' treatment with inhaled steroid was carried out in 10 asthmatic children. Daily doses used were 1 mg orally and 800 mug by inhalation. Nine patients had fewer symptoms, higher peak expiratory flow rates, and a lower bronchodilator requirement on inhaled than on oral therapy. Exercise-induced bronchoconstriction was diminished on inhaled therapy. Five children requested early termination of the oral therapy period because of unacceptable symptoms. Nine parents stated a preference for the period of inhaled therapy. It is concluded that betamethasone valerate is highly effective by inhalation but that a comparable oral dose has no appreciable clinical effect.