What a Foley Catheter Is
The indwelling urinary catheter — why it's placed and how it works.
What is a Foley Catheter?
A Foley catheter is a thin, flexible hollow tube that we insert into your bladder to drain urine. It is held in place by a small, water-filled balloon at the tip inside your bladder. This allows urine to flow continuously into an external collection bag.
Why We Use Them in Hospitals
We use catheters to accurately measure your urine output, which helps us track your organ function during recovery. They are also necessary if you cannot physically get to a restroom due to illness or surgery. In some cases, we use them to keep your bladder empty during procedures or to help heal a wound near the pelvic area.
The Insertion and Maintenance Process
A nurse inserts the catheter using a sterile technique to prevent bacteria from entering the bladder. Once inside, we secure the tubing to your leg to prevent pulling or irritation. You will need to keep the collection bag lower than your bladder at all times to ensure gravity keeps the urine flowing correctly.
Risks and Important Safety Precautions
The primary risk is a catheter-associated urinary tract infection, or CAUTI, which happens when bacteria travel up the tube. We limit how long the catheter stays in place to reduce this risk. If you feel sudden pain, see blood in the tubing, or notice no urine in the bag for several hours, tell your nursing team immediately.
Last reviewed August 14, 2026