Small red dots on the arm may be the manifestation of perifollicular keratosis, and may also be cherry angioma and other diseases. 1. If the small red dots on the patient’s arm without pain and itching and other uncomfortable symptoms, and mostly occur in the upper arm extension, touch the texture is relatively hard, is likely to be the performance of perikeratosis, this disease is related to heredity, is due to the patient’s local skin follicle mouth keratinization caused by abnormalities, you can not do the treatment. 2. If the patient does not have other symptoms such as itching and pain, and the small red dots fade when pressed, and then turn red after lifting the hand, then it may be cherry angioma, which will not have health damage to the patient. If the small red dots on the patient’s arm have pain and itching, it may be eczema, contact dermatitis, purpura and other diseases. If the small red dots on the arm are not relieved or other symptoms appear, you should go to the hospital in time to give targeted treatment.