Chronic interstitial nephritis is treated with different drugs depending on the cause and comorbidities. If it is caused by chronic pyelonephritis, levofloxacin can be chosen; if it is caused by nephrotoxic drugs, the related drugs need to be stopped; if it is caused by obstruction, the obstruction needs to be lifted; if it is caused by systemic lupus erythematosus, prednisone acetate can be chosen; if it is combined with hypertension and so on, valsartan can be chosen. The common causes of chronic interstitial nephritis are: obstructive nephropathy and reflux nephropathy, nephrotoxicity, chronic pyelonephritis, autoimmune diseases such as systemic lupus erythematosus, dry syndrome, etc., and for specific causes of the treatment methods and drugs are different. In addition, chronic interstitial nephritis can be combined with anemia and hypertension. For different causes and comorbidities, we can choose to release the obstruction; stop nephrotoxic drugs; anti-infections such as levofloxacin, cefuroxime; cyclophosphamide, prednisone acetate, tretinoin and other drugs. For comorbidities such as anemia and hypertension, supplemental erythropoietin, valsartan and nifedipine extended-release tablets can be given. If diagnosed with chronic interstitial nephritis, it is recommended to go to a regular hospital as early as possible, follow the doctor’s instructions for standardized treatment, and the above medication must be used in accordance with the doctor’s instructions.