Chronic low-grade fever can only be cured by identifying the cause of the disease and carrying out targeted treatment. General tuberculosis, lupus erythematosus, lymphoma, etc. can cause long-term low fever, these are some chronic diseases, it is recommended that patients with long-term low fever go to the hospital as soon as possible to find out the cause of the disease, the treatment of different diseases are also different, you need to be guided by a doctor to use medication. 1. Tuberculosis: Its typical symptoms are night sweats (abnormal sweating after going to sleep and stop sweating after waking up) and low fever in the afternoon. It can be treated by medication (isoniazid, rifampicin, pyrazinamide), and anti-tuberculosis treatment should pay attention to the early, combined, appropriate amount, regular, and the whole process of the use of drugs, and should not be arbitrarily discontinued. 2. Lupus erythematosus: Lupus erythematosus can also cause prolonged low-grade fever and is an autoimmune disease. It is an autoimmune disease. The treatment is mainly hormone plus immunosuppressant (prednisone, cyclophosphamide, azathioprine). 3. Lymphoma: long-term low fever of lymphoma is also its obvious symptom. At present, the treatment of lymphoma is still mainly based on chemotherapy, such as vincristine, Zoerythromycin and so on. Long-term low fever should be treated in time, and the drugs should be used according to the doctor’s prescription.