Urinary Catheter Types
and Sizes and How to Choose

Published 2019/08/05​

Table of Contents

There are three main types of urinary catheters—intermittent catheters, indwelling catheters, and external catheters. A urinary catheter’s size is determined by the girth of the catheter, which is measured on the french scale. This article will help you understand the different types of catheters and figure out what your catheter size should be.

What is a urinary catheter?

A urinary catheter, when referring to an intermittent catheter or indwelling catheter, is a hollow tube that is inserted into the bladder to drain urine.


Intermittent catheters are used to treat urinary retention, and indwelling catheters are used to treat urinary retention and urinary incontinence.


An external catheter, which is also a type of urinary catheter, does not enter the body. It has a condom-shaped receptacle that wraps around a man’s penis and a thin tube that leads from the receptacle into a urine collection bag strapped around the leg. It does not treat urinary retention, only urinary incontinence.

What are the different types of catheters?

01 Intermittent Catheters

Intermittent catheters are catheters that are inserted into the bladder for a short duration to empty the bladder of urine. They’re used intermittently—several times throughout the day. The catheter can be inserted through the urethra or a man-made channel between the bladder and an opening on the abdominal wall. 


People who use intermittent catheters often have urinary retention as the result of another medical condition such as neurogenic bladder syndrome (SCI, MS, stroke, diabetes, etc), enlarged prostate, bladder exstrophy, and pelvic organ prolapse. 


For people who have undergone urinary diversion surgery and have an Indiana pouch, Kock pouch, or other forms of continent catheterizable urine pouches, they also rely on intermittent catheters to drain their urine.

Most intermittent catheters on the market are single-use, which means they need to be disposed of after being used one time. Never reuse single-use catheters as this will greatly increase your risk of catheter-associated UTI (CAUTI). 


Some intermittent catheters are made to be reusable, but a study finds that washing reusable catheters with antibacterial soap still resulted in 44% of them being contaminated with bacteria. In contrast, single-use catheters are completely sterilized before they’re distributed. 


Intermittent catheters allow people to self-catheterize only when they need to, which means the rest of the time people can function as usual, and their independence is not impeded.  

02 Pre-lubricated, Intermittent Catheters

Among intermittent catheters, some need the user to apply lubrication onto the catheter, and some come pre-lubricated. The most common type of pre-lubricated catheter is the hydrophilic catheter.


The hydrophilic catheter comes very slippery and smooth once it comes into contact with water. This is because it has a special polymer coating that can bind water onto the catheter. The hydrophilic catheter greatly reduces friction and potentially reduces friction-related catheterization injuries.

03 Advanced, Travel-friendly, Pre-lubricated Intermittent Catheters

CompactCath’s catheters have been innovated to not only be pre-lubricated but also extremely compact and discrete. This makes them great companions for long or short trips, going to work, or going on a night out. 


CompactCath’s catheters are pre-lubricated with silicone oil. They can be used right out of the package, which is different from hydrophilic catheters which need the additional step of rinsing with water. Silicone oil also has anti-microbial properties, which means it can suppress or kill certain fungi, viruses, and bacteria. This is a unique property that hydrophilic catheters do no have.


CompactCath’s catheters are also no-touch, which means you don’t have to touch the tube of the catheter while you’re inserting it (click to see how to insert a no-touch catheter). A study has found that no-touch catheters decrease the risk of bacterial contamination.

04 Indwelling Catheters

Indwelling catheters are flexible medical grade rubber or plastic tubes that are inserted into the bladder and made to remain there to provide continuous urinary drainage.


Indwelling catheters can be used to treat urinary retention and incontinence. It is also commonly used to empty the bladder during and immediately after surgery when someone is bedridden and has lost control of their bladder. 


Compared to the intermittent catheters, indwelling catheters may hinder mobility since the catheter stays inside the person’s body all the time. However, oftentimes, people who use indwelling catheters already have limited mobility due to other reasons such as acute illnesses or spinal cord injuries.  


There are two kinds of indwelling catheters, urethral and suprapubic. A urethral indwelling catheter is inserted through the urethra into the bladder, and a suprapubic catheter is inserted through an incision on the abdominal wall into the bladder. The latter may sound more invasive, but it poses a smaller risk of infection, is easier to cover with clothes, can help avoid urethral damage, and is easier to take care of for people already in wheelchairs.


Your doctor will decide which kind of indwelling catheter you receive and for how long depending on your individual circumstance. 

05 External Catheters

External catheters, or condom catheters, are used by men to treat urinary incontinence. This type of catheter consists of a flexible sheath that slides over the penis just like a condom with a tube connected to a bag. Many men find this style to be a great alternative to the more invasive catheters that require insertion through the urethra. 


External catheters are only used for urinary incontinence, not urinary retention, and they’re only available for men. Condom catheters can manage spontaneous leakage, but if the person cannot urinate on their own, external catheters would not work. 

What is the french scale for catheters?

1 “French” or “Fr” is equivalent to 0.33 mm = .013″ = 1/77″ in diameter. The size in French units is roughly equal to the circumference of the catheter in millimeters. 


French sizes only apply to intermittent and indwelling catheters. External catheters’ sizes are measured in millimeters (mm), depending on the diameter of the condom-shaped receptacle. 


The average catheter size used by adult men range from 14fr to 16fr, and most men use 14fr catheters. 


The average catheter size used by adult women range from 10fr to 12fr, and most women use 12fr catheters.

Catheters are color-coded based on their french sizes:


  • Size 10 french: black
  • Size 12 french: white
  • Size 14 french: green
  • Size 16 french: orange
  • Size 18 french: red

The ready-to-use catheters
makes timed-voiding easier

CompactCath offers discreet, compact, and easy-to-use intermittent catheters in various tips and sizes.

Do you want to try our samples?