The clinical effectiveness of beclomethasone dipropionate (BDP) aerosol and adrenal function after withdrawal of oral corticosteroid therapy were evaluated in 32 severely steroid-dependent asthmatic patients. Twenty-four of 28 patients were able to discontinue oral glucocorticosteroid therapy, while four failed to do so. Ventilatory studies showed no substantial changes at the end of six months' BDP treatment. In 24 patients, adrenal insufficiency was present before BDP therapy was started. In 20 of those patients, the response of cosyntropin returned to normal two months after discontinuation of systemic steroid treatment and administration of BDP.