Small and itchy bumps on the hands may be related to herpes sweat, urticaria, contact dermatitis and ringworm. 1. Sweat herpes: also known as sweaty eczema, is a kind of skin disease due to a variety of factors, in the clinical mainly manifested in the palm area of the skin appeared in the small blisters, and accompanied by intense itching. 2. Urticaria: a skin disease mainly characterized by hives, related to contact with allergens, accompanied by intense itching during the onset of the disease. 3. Contact dermatitis: it is a kind of allergic reaction of local skin after contacting irritating objects, which is manifested in the clinic as limited rash and itching symptoms. 4. ringworm: is a fungal infectious disease, and has a certain degree of contagious, in the clinical mainly for the skin pimples, small blisters or vesicles, and will be accompanied by itching discomfort. Itchy bumps on the hands may also be other reasons, it is recommended that the patient to the hospital in a timely manner, to clarify the cause of the disease, under the guidance of the doctor standardized treatment.