The phenomenon of excessive urination after a few hours of infusion may be physiological causes, or it may be pathologic causes, such as urinary tract infections, neurogenic urinary frequency, and so on. 1. Physiological reasons: After infusion of large amounts of liquid into the body, some people due to the body’s fast metabolism, which may appear infusion of urine frequency phenomenon, its a normal phenomenon, generally do not need special treatment. 2. Pathologic causes: (1) urinary tract infections: including urethritis, cystitis, etc., most of the bladder irritation symptoms such as urinary frequency, urinary urgency and urinary pain. (2) Neurogenic urinary frequency: mostly due to mental, psychological and environmental factors and other factors caused by polyuria, can be manifested as frequent urination and other symptoms, may also appear after infusion of a few hours of urinary phenomenon. Increased urination after infusion may also be caused by other factors, if the above symptoms and exclude physiological reasons, it is recommended to enter the hospital to identify the cause and actively cooperate with the doctor for treatment.