Histamine is a key mediator in allergic diseases, where it exerts most of its effects through the H1 receptor and to a less extent the H2 receptor. H1-antihistamines provide rapid relief of many of the allergic symptoms and are considered the main stay of treatment of allergic rhinoconjunctivitis and urticaria. H1 antihistamines comprise first generation (old) and second generation (new) H 1 antihistamines with different pharmacological aspects, efficacy and safety profile. Few studies dealt with H1 antihistamines in pediatric population. This review will highlight the characteristics of H1 antihistamines and their indications in pediatric allergic disorders.Egypt J Pediatr Allergy Immunol 2012; 10(1):3-1
