The causes of high urea nitrogen can be divided into pre-renal, renal and post-renal, as follows: 1. Pre-renal: the main cause is heart failure, which requires diuretic and cardiac treatment. 2. Renal: caused by various kidney diseases, such as nephritis, nephropathy and renal failure, which can lead to high urea nitrogen, which requires different treatment methods according to different diseases. . 3, post-renal: mainly urinary tract obstruction, a common urethral obstruction is a kidney stone, another is a kidney tumor, and prostate hyperplasia. If it is a kidney stone, it requires lithotripsy or surgery to remove the stone. If it’s a urological tumor, this is when anti-tumor treatment is needed. If it is prostatic hyperplasia, anti-prostatic treatment is needed. Urea nitrogen is a metabolic product of protein, typically producing 0.3g of urea per gram of protein metabolized. The kidneys are also the main excretory organ of urea nitrogen, which is reabsorbed in all segments of the renal tubules after filtration from the glomerulus.