It must be emphasized that famotidine and other antihistamines are drugs of choice for prevention and treatment of Kounis syndrome [104], as well as for prevention of myocardial ischemia/reperfusion injury induced by histamine H2 receptor activation [105] and further for peripheral vessel leakage prevention that is incriminated for the shock in anaphylaxis. Here, HRH2 is linked to myocardial ischemia.