Keywords: exogen Cushing syndrome, nasal steroids

Abstract: Glucocorticoids have been largely used in the clinical practice since the early 1950s. While unwanted side effects related to its oral or parenteral use are well known, there are not many reports about such effects when glycocorticoids were used topically. We relate the case of a sixteen-year-old boy with allergic rhinitis who developed exogenous Cushing syndrome after abusive use of a nasal spray containing dexamethasone in a daily dose varying from 0.5-0.7mg during 4 years. Once the diagnosis of exogenous Cushing syndrome was established, the spray containing dexamethasone was substituted by another one without steroids associated with the prescription of dexamethasone tablets in progressively lower doses. About 3 month later, when complete restoration of the hypothalamic-pituitary-adrenal axis was observed, the tablets were discontinued. We would like to emphasize the importance of a strict follow-up of all patients with chronic use of any drug containing glycocorticoids; it is recommended in some cases to determine urinary free or plasmatic cortisol after the new low-dose (1mcg) ACTH stimulation test, in order to come to the diagnosis of incipient adrenal insufficiency, which could offer some danger in the presence of mild to moderate stress. Since the possibility of severe systemic side effects remains with the use of nasal steroids, we should whenever feasible prefer the use of glycocorticoids with lower bioavailability and emphasize the importance of respecting the dose and the time prescribed.