A Foley bag is the collection bag attached to a Foley catheter, a flexible tube inserted into the bladder to drain urine. The bag collects and holds urine that flows continuously from the bladder through the catheter tubing. Most people encounter one after surgery, during a hospital stay, or when managing a condition at home that makes it difficult to urinate normally.
How the System Works
The Foley catheter is a thin, flexible tube that a healthcare provider threads through the urethra and into the bladder. Once in place, a small balloon at the tip is inflated with sterile water to keep the catheter from slipping out. The other end of the catheter connects to a drainage bag, and urine flows through the tubing into the bag by gravity. This is why the bag always needs to sit lower than the bladder: if it’s positioned higher, urine can’t drain properly and could flow backward into the bladder, raising the risk of infection.
The system drains continuously. Unlike using the toilet, there’s no sensation of needing to “go.” Urine simply moves through the tubing as the bladder produces it, and you empty the bag at regular intervals through a valve or spout at the bottom.
Leg Bags vs. Bedside Bags
There are two main types of Foley bags, and many people use both over the course of a single day.
- Leg bags are small, flat bags that strap to your thigh or lower leg under your clothing. They’re designed for daytime use and are discreet enough to wear while going about normal activities. The tradeoff for their smaller size is that they fill up faster, typically needing to be emptied every two to four hours.
- Bedside drainage bags (also called night bags) are roughly double the capacity of a leg bag. They hang on a stand next to your bed and hold enough urine to last through the night, usually about eight hours, so you only need to empty them once in the morning.
The typical routine is to wear a leg bag during the day, then switch to a bedside bag before sleep. Swapping between the two is straightforward: you disconnect the tubing from one bag and connect it to the other, keeping the connection point clean.
Why Someone Might Need One
Foley bags aren’t just for people recovering from surgery, though that’s one of the most common reasons. The CDC lists several specific situations where an indwelling catheter is appropriate:
- Urinary retention or blockage, where the bladder can’t empty on its own
- Monitoring urine output in critically ill patients
- During and after surgery, especially procedures on the urinary tract, long operations, or those involving large amounts of IV fluids
- Wound healing, particularly for open wounds in the sacral or perineal area in patients who are incontinent
- Prolonged immobilization, such as after spinal injuries or multiple pelvic fractures
- End-of-life comfort care
Some people use a Foley catheter and bag for a few days after a procedure. Others rely on one for weeks or months due to chronic conditions like neurogenic bladder or severe urinary retention.
Emptying and Keeping It Clean
Proper emptying is one of the most important things you can do to avoid problems. For a leg bag, plan on emptying it every two to four hours, or before it gets completely full. A bedside bag can typically go a full night. Wash your hands thoroughly before and after handling the drainage valve, and avoid letting the spout touch the toilet rim or collection container.
Keeping the system closed is critical. Every time you disconnect the tubing or open the drainage port, there’s an opportunity for bacteria to enter. The connection between the catheter tubing and the bag should stay sealed as much as possible. When you do switch between a leg bag and a night bag, clean the connection point and work quickly.
Infection Risk and Prevention
Catheter-associated urinary tract infections (CAUTIs) are one of the most common healthcare-associated infections, and the drainage bag itself is a key entry point for bacteria. Germs can travel into the urinary tract either along the outside of the catheter or up through a contaminated bag or tubing connection.
Several factors increase the risk: how long the catheter stays in, older age, having diabetes, and errors in care like not keeping the drainage system closed or not using clean technique. The single most effective prevention strategy is removing the catheter as soon as it’s no longer medically necessary. For people who need one long-term, keeping the bag below the bladder at all times, emptying it regularly, and maintaining clean connections all reduce the chances of infection.
Signs of a possible infection include cloudy or foul-smelling urine, fever, pain in the lower abdomen or back, and urine that appears bloody. These warrant prompt medical attention, especially in someone with a catheter already in place.
Living With a Foley Bag Day to Day
For people managing a catheter at home, the daily reality is more manageable than it might sound. Leg bags fit under loose pants, skirts, or shorts and are held in place with straps or fabric sleeves on the thigh or calf. Most people find they can work, run errands, and socialize without anyone knowing the bag is there. The main adjustment is building in time to empty the bag regularly and carrying supplies for hygiene when you’re away from home.
Sleeping with a bedside bag is generally straightforward. The bag hangs from a stand or hooks onto the bed frame, keeping it below bladder level. Because it holds roughly twice as much as a leg bag, you can sleep through the night without getting up to empty it. In the morning, you drain the bedside bag, clean up, and switch back to your leg bag for the day.
Staying hydrated is still important, even though it means more frequent emptying. Adequate fluid intake helps flush the system, keeps urine dilute, and may lower infection risk. Restricting fluids to avoid dealing with the bag can backfire by concentrating the urine and creating a friendlier environment for bacteria.