Subacute thyroiditis is a self-limiting disease that usually resolves in 1-3 months, depending on the severity of the symptoms, whether the symptoms are combined with thyroid function abnormalities, and whether permanent hypothyroidism remains. Subacute thyroiditis is a subacute inflammation of the thyroid gland that is self-limiting, i.e., as the course of the disease prolongs, the symptoms will gradually resolve until they return to normal. The main symptoms of subacute thyroiditis are fever and neck pain. In the early stages of the disease, the main symptoms are fever and neck pain. However, as the disease progresses, these symptoms gradually diminish and return to normal. In the middle stage of subacute thyroiditis, some patients may experience hypothyroidism, which is a decrease in basal metabolic rate, a decrease in body temperature, fear of cold, weight gain, and emotional indifference. Then as the condition gradually improves, thyroid hormone secretion gradually resumes, and the symptoms of hypothyroidism will gradually decrease. Generally, patients usually recover spontaneously within 1 month or less than 3 months, and a few patients will have more than 3 months. Patients with subacute thyroiditis should not be overly anxious and should pay attention to rest to promote self-healing. If the symptoms of subacute thyroiditis persist for a long time, it is recommended to consult a doctor in time and follow the doctor’s instructions for examination and treatment, not to take medication without authorization.