Urinary retention, or a bladder not emptying all the way, can be caused by urinary tract obstruction as well as overactive nerve signals between the brain and bladder, according to the National Kidney and Urologic Diseases Information Clearinghouse. Weak bladders sometimes lead to urinary retention, and additional causes include urinary tract infections, antihistamine medications and antidepressants, according to the National Kidney and Urologic Diseases Information Clearinghouse.
According to MedicineNet, an inability to completely empty the bladder is referred to as chronic urinary retention. Individuals with chronic urinary retention often have a constant urge to urinate and feel as if they still need to urinate immediately after using the restroom. Frequent urination is also common. MedicineNet explains that chronic urinary retention is most common in men with enlarged prostate glands, but it can be present in individuals of all ages.
Medtronic explains that there are two types of urinary retention. Obstructive urinary retention is caused by obstructions, such as kidney stones, that prevent the free flow of urine, and non-obstructive urinary retention can be caused by nerve issues or weak bladder muscles. Common causes of obstructive urinary retention include cancer, enlarged prostate and kidney stones, and common causes of non-obstructive urinary retention include stroke, impaired function of the muscles or nerves caused by anesthesia or certain medications, spinal cord injuries, injury to the pelvis and childbirth, according to Medtronic.