What is the reason why the back of the hand has a pimple and itches again

Small pimples on the back of the hand accompanied by itching, to consider papular urticaria, which is caused by an insect bite, skin lesions manifested as erythema papules, or herpes, itching intense, there may be eczema. The cause of eczema is more complex, but the hand local eczema may be related to contact with irritating substances, this is a local allergic reaction, to do anti-allergic treatment. Can be short-term external application of hormone ointment, to prevent contact with irritating substances. Of course, there may be fungal infection, can also show this situation. Therefore, it is best to go to the hospital dermatology department, under the guidance of a specialist, a clear diagnosis to timely medication treatment.