Histamine plays an important role in many kinds of dermatoses through its four receptors,i.e.,H1R,H2R,H3R and H4R.The biological activities of H2R,H3R and H4R are different,and their ligands exhibit different roles in dermatoses.H2R antagonists are mainly used in combination with H1R antagonists to treat chronic urticaria,as well as cutaneous warts,herpes zoster,herpes simplex,androgenetic alopecia and acne; H3R ligands may have antinociceptive,antipruritic and anti-anaphylactic properties; H4R antagonists have shown anti-inflammatory and anti-pruritic effects in various models of allergic inflammatory diseases.