The authors looked for undesirable side-effects in prolonged treatment with beclomethasone dipropionate aerosol (BDP) at the daily dose of 400 microgram in asthmatic children. Growth in height was not impaired, the height gain (5.35 +/- 4.06 cm) not being statistically different from the theoretical gain (5.46 +/- 2.94 cm) (t : 1.33 0.20 less than p less than 0.01). Testing the corticotropic chain at pituitary level by the L8VP test did not reveal any decrease in patients treated by BDP alone (delta of elevation of cortisolemia; 9.08 +/- 2.79 microgram/100 ml, not very different from the controls 9.79 +/- 4.32 microgram/100 ml). On the other hand, the results in patients with continuous or alternating conventional corticotherapy showed a corticotropic decrease (delta of elevation : 5.39 +/- 4.53 microgram/100 ml, a significant difference from the controls t : 7.54 p less than 0.001). In 5 of these observations, the repetition of L8VP testing revealed the progressive restauration of the corticotropic function together with the decrease and the stopping of conventional corticotherapy. The average cortisolemia of patients definitively off corticotherapy, before and after L8VP, was not significantly different from that of controls. The elevation delta of cortisolemia of deprived patients (9.30 +/- 4.92 microgram/100 ml) become comparable to that of normal controls (9.79 +/- 4.32 microgram/100 ml. The analysis of the main literature data, in agreement with the results presented here, showed that prolonged treatment with BDP had no harmful effect on height growth. There was no corticotropic decrease in a child unsubjected to previously conventional corticotherapy or after completely stopping the treatment.