You can distinguish between allergy and scabies bite by symptoms and examination. 1. Symptoms: Scabies is a parasite that causes pimples, herpes and intense itching after being bitten, and this itching is usually worse at night, and the damaged skin is usually in the folds of the skin, such as the finger cracks, etc. Allergies can also cause pimples and itching, but the symptoms are usually aggravated by exposure to allergens. Allergies can also cause pimples and itching, but usually in the exposed parts of the skin, and the symptoms are aggravated after contact with allergens. 2. Examination: allergic reactions can be clearly diagnosed by serum total IgE and specific IgE, scabies can be observed directly through dermoscopy, lesions can be found parallel to the body surface of the tunnels, tunnels may also have scabies feces, through the staining examination can also be found scabies or eggs. If the skin symptoms, can not distinguish between allergies and scabies bites should go to the hospital for a detailed examination by the doctor to identify, and then for the cause of the symptomatic treatment.