The causes of a lot of small red dots on the back of the feet are itchy, including tinea pedis, eczema, allergic purpura, scabies, etc., which can be treated with medication. 1. Tinea pedis: If the fungal infection triggers the small red dots on the back of the feet, you can give local topical bifonazole solution, econazole nitrate ointment, or oral itraconazole and other antifungal drug treatment. 2. Eczema: If the skin on the back of the feet is irritated by inflammatory factors, it can be treated with isacridine solution or glucocorticoid drugs. 3. Anaphylactic purpura: If the small red dots are caused by allergic reactions to sensitizing substances, anti-allergic treatment with drugs such as promethazine hydrochloride can be used. 4. Scabies: for scabies infection caused by small red spots, this time you need to give 10% clomid cream, sulfur cream coated to kill scabies treatment. Finally, there are a lot of small red dots on the back of the feet is very itchy phenomenon should avoid scratching, timely medical treatment, under the guidance of the doctor to use drugs.