[Medical Q&A] What are the dangers of holding urine for a long time?

Planner: Chinese Medical Association

Reviewer: Zhang Kai, Chief Physician, Peking University First Hospital

Holding urine for a long time can cause urination difficulties: when the urine stored in the bladder reaches a certain amount, the stretch receptors in the bladder will be excited, and the impulse to urinate will be transmitted to the lower central nervous system, that is, the spinal cord, through the afferent nerves; then the impulse is further transmitted to the brain, and the brain knows that it is necessary to urinate, and the person will feel the urge to urinate. Holding urine for a long time will cause fatigue of the stretch receptors on the surface of the bladder. After fatigue, the impulse will be transmitted to the receptors again, and the excitement will be reduced, resulting in weakened detrusor contraction. At the same time, holding urine for a long time will also cause long-term stretching of the bladder muscles. If it contracts suddenly, it will immediately return to the physiological state.

Holding urine for a long time can also cause urinary tract infection: bacteria will flow back from the urethra into the bladder, causing urinary tract infection, and in severe cases even kidney infection.

Holding urine for a long time may also cause bladder tumors: studies have shown that people who have the habit of holding urine have a 3 to 5 times increased risk of bladder cancer.

In addition, urinary tract infections and bladder tumors may also lead to urination dysfunction, that is, "cannot store urine well, and can't excrete it, and it's endless after excretion", including frequent urination, urgency, difficulty urinating, hesitation to urinate, thinning of the urine stream, urethral pain after urination, dripping after urination, etc., affecting the quality of life.