Glucocorticoids could be responsible for allergic symptoms correlated to an Ig-E mediated hypersensitivity mechanism. We describe the case of an anaphylactic reaction in a professional nurse, occurring after an intramuscular administration of Betamethasone. After performing skin prick tests, intramuscular tests and patch tests we concluded that the patient had Ig-E mediated sensitization. She was prescribed oral Prednisone and Deflazacort and shows good tolerance of these drugs. This demonstrates that in these patients it is possible to administrate glucocorticoids without the changes in the sites indicated by Wilkinson. Nevertheless, our patient showed a negative allergy test for Dexamethasone disodium phosphate, and in those patients sensitized to fluorinated glucocorticoids, tolerance to other glucocorticoids is not so easily predictable as in patients with hypersensitivity to first generation steroids or in corticosteroid contact dermatitis, according to the four patterns of cross-reactivity proposed by Coopman and Dooms-Goossens.