Small red spots on the back of the feet may be caused by purpura, contact dermatitis, athlete’s foot, etc. Drugs and surgical treatments can be chosen according to the cause. 1. Anaphylactic purpura: Anaphylactic purpura may be caused by microbial infection or food allergy, which leads to the perverse reaction of blood vessels and causes red spots on the back of the feet. Patients can take cetirizine tablets, loratadine tablets and other drugs under the guidance of the doctor, which can play an anti-allergic role. 2. Contact dermatitis: Contact dermatitis can be caused by contact with chemicals or plant and animal allergens, resulting in small red spots on the back of the feet, and the border is relatively clear. You need to apply medicines such as glycerine lotion and mometasone furoate cream, which can relieve the skin discomfort. 3. Tinea pedis: Tinea pedis is caused by fungal infection of the skin of the feet, resulting in small red spots on the back of the feet, and there will be peeling, blisters and so on. You can take antifungal medication, such as itraconazole capsules and terbinafine hydrochloride tablets, to help the skin recover. Red spots on the back of the feet also need to consider eczema, folliculitis, etc., the patient needs to go to the hospital, under the guidance of the doctor to do the appropriate identification and symptomatic treatment, so as to avoid the private use of drugs on the body to cause harm. All of the above medications should be used in accordance with the doctor’s instructions.