Extremity pain, weakness and emaciation may be caused by hyperthyroidism (low iodine diet, medication, iodine 131 treatment, etc.), systemic lupus erythematosus (avoiding bright light and ultraviolet rays, glucocorticoids, immunosuppressant treatment, etc.), which need to be analyzed specifically. 1. Hyperthyroidism: Hyperthyroidism can be characterized by aching limbs, weakness, emaciation, accompanied by palpitations (accelerated heartbeat, often accompanied by panic), profuse sweating, etc. It requires a low iodine diet as well as treatments such as oral medications (e.g., methimazole, propylthiouracil, etc.), iodine-131, or surgical resection of the thyroid gland. 2. Systemic lupus erythematosus: Systemic lupus erythematosus can be characterized by limb pain, weakness, emaciation, discoid erythema, mouth ulcers, etc. It is necessary to avoid bright light and ultraviolet rays, take sufficient rest, relax, and take glucocorticosteroids (e.g., prednisone, etc.) and/or immunosuppressant drugs (e.g., cyclophosphamide, etc.) at the same time. It is recommended to clarify the cause of the disease as soon as possible and treat it in time to avoid delaying the disease.