A Foley catheter is a flexible tube inserted through the urethra into the bladder to drain urine, and the process typically takes only a few minutes. The procedure follows a strict sterile technique to prevent infection, and while it can cause brief discomfort, the use of numbing gel significantly reduces pain during insertion.
What a Foley Catheter Looks Like
A Foley catheter is a thin, flexible tube with two channels running through it. One channel drains urine from the bladder into a collection bag. The second channel connects to a small balloon near the tip, which gets inflated with water once the catheter is inside the bladder to keep it from slipping out. The catheter connects to a drainage bag that either straps to your leg or hangs from the side of your bed.
Catheters are measured using the French scale, a universal sizing system based on the tube’s outer diameter. Most adult women use sizes ranging from 12 to 16 French, while most adult men use 14 to 18 French. A smaller number means a thinner tube. Your care team selects the smallest size that will drain effectively.
Preparation Before Insertion
You’ll lie on your back for the procedure. Women are typically asked to bend their knees with feet flat, which gives the person inserting the catheter a clear view of the urethral opening. Men lie flat in a standard position.
The clinician opens a sterile catheter kit, which contains the catheter, gloves, antiseptic solution, lubricant, a syringe filled with sterile water, and a drape. Everything is handled carefully to avoid introducing bacteria. The clinician puts on sterile gloves and places a drape over your thighs and around the genital area, creating a clean workspace.
Before anything touches the urethra, the area around the urethral opening is cleaned with an antiseptic solution, typically an iodine-based prep. For women, the labia are gently separated and the antiseptic is applied from front to back. For men, the tip of the penis is cleaned starting at the urethral opening and moving outward in a circular motion. This step is repeated several times with fresh applicators.
How Lubricant and Numbing Gel Help
The catheter tip is coated with a water-soluble lubricant to reduce friction during insertion. In many cases, a gel containing a local anesthetic (lidocaine) is used instead of plain lubricant. Research comparing the two found that patients who received lidocaine gel reported pain scores of about 1.4 out of 10 during catheter placement, compared to 3.9 out of 10 with plain lubricant. That’s a meaningful difference in comfort, especially for procedures involving the urethra.
For men, the numbing gel is often squeezed directly into the urethra before the catheter goes in, since the male urethra is significantly longer. For women, the gel is typically applied to the catheter tip itself.
The Insertion Process
The actual insertion differs slightly between men and women because of anatomy. The female urethra is about 3 to 4 centimeters long, located between the clitoris and the vaginal opening. The male urethra is roughly 20 centimeters long, passing through the prostate gland before reaching the bladder. This difference means the catheter needs to travel much farther in men, and the procedure takes slightly longer.
For Women
The clinician separates the labia with one hand to clearly see the urethral opening. With the other hand, the lubricated catheter is gently guided into the urethra. Because the female urethra is short, the catheter only needs to advance a few centimeters before reaching the bladder. You may feel pressure or a brief stinging sensation, but the insertion is quick.
For Men
The clinician holds the penis gently lifted at a 60 to 90 degree angle with one hand, which straightens out the natural curve of the urethra and makes insertion easier. The lubricated catheter is then slowly threaded into the urethral opening with the other hand. The catheter is advanced steadily until it reaches its full length, at which point the hub of the catheter meets the tip of the penis. Men often feel pressure as the catheter passes through the prostate area, which is the narrowest part of the path. Slow, steady breathing helps relax the pelvic muscles and makes this part easier.
Confirming Placement and Securing the Catheter
The key sign that the catheter is in the right place is urine flowing through the tube. Once urine appears in the drainage tubing, the clinician knows the tip has reached the bladder. If urine doesn’t appear right away, gentle pressure on the lower abdomen may help. The balloon is never inflated until urine flow is confirmed, because inflating it while still in the urethra could cause injury.
To inflate the balloon, the clinician attaches a syringe of sterile water to the catheter’s second port and slowly pushes the water in. Sterile water is the standard filling solution. You may feel a brief sensation of fullness or a mild urge to urinate as the balloon expands inside the bladder. Once inflated, the catheter is gently pulled back until the balloon rests against the bladder neck, holding it securely in place. The drainage bag is then connected and positioned below the level of the bladder so urine flows by gravity.
What It Feels Like
Most people describe the insertion as uncomfortable rather than truly painful, especially when numbing gel is used. The strongest sensation usually happens in the first few seconds as the catheter enters the urethra. For men, the moment the catheter passes through the prostate region can feel like strong pressure or a sudden urge to urinate. This passes quickly.
Once the catheter is in place, you may have a persistent feeling of needing to urinate. This is normal and typically fades within 15 to 30 minutes as your body adjusts to the catheter’s presence. Some people also experience mild bladder spasms, which feel like sudden cramping. These tend to settle down on their own.
When Insertion Is Difficult
In some men, an enlarged prostate can make it hard to pass a standard straight-tipped catheter. When this happens, a coudé catheter may be used instead. This is a catheter with a slight upward curve near the tip that mimics the natural curve of the male urethra through the prostate. The curved design allows it to navigate past the obstruction with less force and less risk of injuring the urethral lining. The same type of curved catheter can also help in women whose urethral opening has shifted forward and is hard to access with a straight tip.
When a Catheter Should Not Be Inserted
There are situations where inserting a urethral catheter could cause serious harm. Blood visible at the urethral opening is the most important warning sign, as it may indicate an injury to the urethra itself. Other contraindications include visible blood in the urine, signs of urethral infection, or a known urethral injury (sometimes seen after pelvic fractures). In these cases, imaging of the urethra is performed first to confirm it’s safe before any catheter is placed. If the urethra is damaged, urine drainage is accomplished through a different route, typically a catheter placed directly through the abdominal wall into the bladder.