Inserting a urinary catheter or feeling the urge to urinate may be a physiological reaction, but it may also be caused by inflammation of the urinary system such as urethritis, cystitis or bladder spasm. 1. Physiological reaction: after the urethra is inserted into the urethra, some patients may feel the urge to urinate, which is a normal physiological reaction, and there is usually no other abnormality. 2. Urethritis: If you do not pay attention to urethral hygiene when inserting a urinary catheter, the bacteria will enter and cause urethritis, which will lead to symptoms such as frequent urination, urgency and incomplete urination. 3. Cystitis: It may be related to the long time of inserting the urinary catheter, if the urinary catheter is not removed for a long time, the bladder will be infected by bacteria, which may cause irritation reaction, so most patients will have obvious desire to urinate. 4. Bladder spasm: after inserting the urinary catheter, it may cause spasm of bladder sphincter or smooth muscle, which may cause frequent urination, urgency and other symptoms. You should pay attention to urethral hygiene during urethral insertion and insist on washing with warm water, and consult your doctor promptly if you have any adverse reactions.