Under normal circumstances, it takes about 1-2 hours for the bladder to have the urge to urinate after drinking water. After drinking water, water enters the esophagus, goes to the stomach and intestines, and is absorbed in the small intestine and then enters the bloodstream, and then through the bloodstream to the glomerulus, and after the filtration function of the glomerulus, and the reabsorption function of the renal tubules, urine is finally formed. From the renal papilla to reach inside the kidney, and then all the way down through the renal pelvis, ureter and bladder, where the bladder and ureter openings, the process of urine spraying from the ureter openings can be observed under the cystoscope, generally about 5-10 minutes, the ureter openings will spray urine once, each time may be less than 1ml, after the bladder gradually gathered to about 300ml of urine will have the urge to urinate, through the contraction of the bladder sphincter urination function The whole process is relatively long. When there are urinary tract infections, overactive bladder syndrome, and kidney deficiency, the urge to urinate is more frequent and there is not much urine, you need to do the appropriate examination and carry out symptomatic treatment.