Arm long bags like mosquito bites, may be papular urticaria, indeed and mosquito bites and other related, is the skin to mosquito venom an allergic reaction, patients will have obvious itching. Treatment is mainly oral anti-allergic drugs, such as loratadine or levocetirizine, local can be applied externally with glycerite lotion, with astringent and anti-itching effect. It can also be combined with topical hormone creams, such as mometasone furoate cream or Dinaid cream, which have obvious anti-inflammatory effects and promote rash subsidence. Usually pay attention to avoid scratching, if the bite is combined with local infection, you can also apply topical fusidic acid or mupirocin ointment and other anti-bacterial infection treatment.