A small patch of ringworm on the arm can be treated with topical and oral medications. A small piece of ringworm on the arm is a symptom of ringworm, which is a kind of fungal infectious disease of the superficial skin of the body, and the disease is mainly treated with topical antifungal drugs, such as miconazole ointment, terbinafine ointment, naftifine ketoconazole ointment and so on. If the lesions are large, or the rest of the patient’s body also has a fungal infection, then oral terbinafine, itraconazole and other antifungal drugs to treat. In addition, patients should also pay attention to keep the skin dry and clean, and avoid scratching and irritation. If there is a small piece of ringworm on the arm, it is recommended to consult a doctor in time and follow the doctor’s instructions to use medication.