An enlarged bladder, also referred to as bladder hypertrophy, is a medical condition in which the bladder becomes larger than normal, stretches too much, or develops thicker walls. Some people also are born with a bladder that's larger than normal, while in other cases, the condition may develop as the result of an obstruction of some sort. Sometimes, a person may even develop the condition because of an abnormally high volume of urine output or failure to empty the bladder fully on a regular basis.

Since the bladder is larger than normal when it's enlarged, it may stick out past the point it should instead of being held in place by the surrounding body tissues. A bladder that sits outside of it's normal position in this manner may impair the normal function of other organs, such as the kidneys, even though the bladder itself may function normally. Sometimes, this causes the patient's urine flow to become blocked, making it difficult or even impossible for him to empty his bladder fully. Surgery may be required to correct this problem.