[Cushing's syndrome and adrenal suppression by means of intranasal use of dexamethasone preparations].

In two 15-year-old boys with bronchial asthma and allergic rhinitis, bronchospasm disappeared with prolonged use of intranasal dexamethasone ointment and drops respectively. Both showed cushingoid features and total or partial suppression of adrenocortical function. The first patient died during a sudden and unexpected asthma crisis one week after withdrawal of the 0.25% dexamethasone ointment he had been taking at the rate of 1.8 mg/day for one year. The second boy recovered near-normal adrenocortical function 3 months after gradual withdrawal of the 0.01% dexamethasone nose drops he had been on at an average daily dose of 0.5 mg, for the past 6 years. An acute trial in 10 normal volunteers showed marked short-term suppression of endogenous cortisol production after a single intranasal ointment application containing 0.9 mg dexamethasone. Long-term use of dexamethasone preparations on the nasal mucosa may be dangerous by inhibiting hypophyseal-adrenocortical function. Abrupt withdrawal may lead to sudden relapse of a potentially life-threatening accompanying disease such as bronchial asthma.