Overflow incontinence is a type of urinary incontinence. It occurs in men when there is a blockage of the bladder outlet that causes urine to build up in the bladder. Usually the blockage is caused by an enlarged prostate gland (benign prostatic hyperplasia, or BPH), cancer of the prostate, or a narrowing of the urethra. Eventually the bladder becomes so full that it cannot hold any more urine, and the pressure forces excess urine past the obstruction. Overflow incontinence also may occur because the muscle that expels urine from the bladder (detrusor) is too weak to empty the bladder normally. Certain medicines also can cause overflow incontinence.

Overflow incontinence usually is treated with surgery to remove the obstruction, including transurethral resection of the prostate (TURP), a common procedure used to treat BPH. Overflow incontinence also can be treated with medicines. Some men may need a thin, flexible tube (catheter) to allow the bladder to empty normally, either by catheterizing themselves when needed or maintaining a Foley catheter for continuous drainage.