Acute generalized exanthematous pustulosis (AGEP) is an uncommon disease, which presents as a nonfollicular erythematous sterile pustular eruption. More than 90% of the cases are induced by adverse drug reactions, often triggered by anti-infectious systemic drugs. We report a case of itraconazole-induced AGEP in a 22-year-old man, with an assessment of his cytokine/chemokine production and drug-specific cell reactivity. We found that AGEP, like other T cell-mediated drug eruptions, alters the immunological status of the patient, probably favouring T-cell activation, recruitment and regulation. Few cases of itraconazole-induced AGEP have been described in the literature, and to our knowledge, this is the first report in which the cellular immunological features are assessed.