High creatinine alone suggests renal failure, which may be acute renal failure caused by certain nephrotoxic drugs, or chronic renal failure caused by chronic kidney disease. Creatinine is an indicator of kidney function, the normal value is between 30-110μmol/L, if it exceeds 110μmol/L, it is called elevated creatinine, suggesting renal failure, renal failure is divided into acute and chronic according to the time of onset. Acute renal failure is mainly caused by the application of certain nephrotoxic drugs, such as non-steroidal anti-inflammatory drugs, represented by ibuprofen, or certain antibiotics, represented by gentamicin, which are nephrotoxic and can cause a sharp decline in kidney function in a short period of time, leading to acute renal failure. Chronic renal failure is the gradual development of chronic kidney diseases, the more common ones in China are chronic glomerulonephritis, diabetic nephropathy and hypertensive nephropathy, etc.