In the case of unexplained recurrent fever in the elderly, it is recommended to actively seek medical attention, improve the relevant examination, clarify what kind of disease is causing the fever, and take targeted treatment: 1. Oral antibiotics include cephalexin, penicillin V potassium tablets, amoxicillin, etc. Intravenous antibiotics include moxifloxacin, azithromycin, cefoperazone sodium sulbactam, cefazolin, etc. 2. If the patient has fever due to acute cholecystitis or acute appendicitis, surgical treatment can be considered. 3. Pay attention to the drainage of sputum.