Frequent urination refers to an increase in the frequency of urination. Normal adults urinate on average 4 to 6 times a day during the day and 0 to 2 times at night after going to bed; infants urinate 20 to 30 times a day and night. If the number of urination increases significantly and exceeds the above range, it is frequent urination. There are many reasons for frequent urination, which are summarized as follows: 1. Increase in urine volume: When the volume of urine increases, the number of urination will also increase accordingly. Under physiological circumstances, such as drinking a lot of water, eating watermelon, drinking beer, due to the increase in water intake, through the regulation and filtration of the kidneys, the volume of urine increases, the number of urination also increases, there will be frequent urination. In pathological conditions, such as some patients with diabetes mellitus and uremia drink more water, urinate more, and urinate more often. However, there is no discomfort in urination. 2, inflammatory stimulation: when there is inflammation in the bladder, the nerve sensory threshold is reduced, the urinary center is in an excited state, producing frequent urination, and the volume of urine is reduced (<300 to 500 ml/time in adults). Therefore, frequent urination is an important symptom of cystitis, especially in acute cystitis and tuberculous cystitis. Other, such as prostatitis, urethritis, pyelonephritis, pediatric chronic penile head prepuce, and vulvovaginitis, can all present with urinary frequency. In the inflammatory stimulation, often urinary frequency, urinary urgency, urinary pain at the same time, known as urinary tract irritation signs, commonly known as "trichuria". 3.Non-inflammatory irritation: such as urinary stones, foreign bodies, usually urinary frequency as the main manifestation. 4.Reduced bladder capacity: such as occupational bladder lesions, compression by an enlarged uterus during pregnancy, tuberculous bladder contracture or large bladder stones, etc. 5, psychoneurotic urinary frequency: frequent urination is only seen in the daytime, or at night before going to sleep, often due to mental tension or in patients with hysteria. At this time, it can also be accompanied by urinary urgency and painful urination. 6, diseases of the organs adjacent to the urinary system, such as acute appendicitis, pelvic infection, vesiculitis, pelvic tumors, etc.