Background: Kounis syndrome (KS) is defined as a rare cause of an acute coronary syndrome associated with systemic allergic reactions. Objectives:To establish the prevalence of KS among the patients with diagnosis of anaphylaxis and describe clinical features, cardiological and allergological outcomes of patients evaluated in our Allergy Outpatient Clinic. Methods: A retrospective study was carried out in the Allergy Unit of Novara hospital, from January 2008 to March 2020. Skin tests and in vitro tests were performed with suspected etiological agents.Results: We found 9 adults with KS (2%) out of 444 subjects who had experienced anaphylactic reactions (4/9 to hymenoptera stings, 5/9 to drugs). Conclusions:The present study highlights the importance of suspicion of KS that appears not so uncommon in patients with anaphylaxis. KS seems to be a rare disease because unrecognized in diagnosis of anaphylaxis.