Catheters with a hydrophilic coating have the lowest incidence of complications associated with intermittent catheterization.





The hydrophilic coating is a layer of polyvinylpyrrolidone (PVP) located on the surface of some catheters’ tubes, which becomes very slippery in contact with water. It absorbs ten times the weight of the water and creates a slippery layer, similar to the urethral mucosa.

Sterile water is required to activate the hydrophilic coating. Before being inserted into the urethra, the catheter is soaked into water for 30 seconds. It absorbs water and becomes very slippery. Friction of the catheter tube is thereby greatly reduced.

Research has shown

  • In comparison with other methods of lubrication, the hydrophilic coating drastically prolongs the time until the onset of the first symptomatic urinary tract infection (UTI) and lowers their incidence
  • The hydrophilic coating lowers the incidence of urethral bleeding episodes and microhematuria
  • Hydrophilic catheters do not require manual lubrication, which makes them more sterile and consequently less likely to cause an infection. (*Most of them are pre-packaged in sterile water, or with a pouch of sterile water. If not, there is still the danger of contamination by water pouring and contaminated water)

Are there different types of hydrophilic layers?

The longer the drainage time and the longer the catheter is inserted into the urethra, the lower the friction in catheters with a more stable hydrophilic layer will be. The mucous membrane of the urethra acts as a semipermeable membrane, which also absorbs water from the hydrophilic layer.

This means that the urethral mucosa will draw water from the hydrophilic layer and the longer the catheter is inserted into the urethra, the less slippery the layer bill be.

Do not leave a catheter with the hydrophilic layer in the urethra for more than ten minutes as it may start to stick to the urethral wall. The hydrophilic layer is reactivated by soaking in water. However, re-irrigation is not recommended as the catheter is disposable and, if used multiple times, it creates a higher risk of a urinary tract infection.

The quality of hydrophilic layers differs between different catheter manufacturers. Drying time of the hydrophilic layer is important as it determines how long the catheter can be left in the urethra before it dries and sticks to the urethral wall.

Why is lubrication of the catheter with a hydrophilic layer better than gel?

The hydrophilic layer is factory-integrated on the surface of the catheter tube and does not swipe off the surface during catheterization. Even if you try to remove it by hand, you will not succeed.

The opposite happens with catheters to which gel is applied, since by adding friction to the surface of the tube (for example when inserting a catheter into the urethra) the gel is wiped off the surface and the catheter tube remains dry.

This is especially important in men who have a long urethra, as the gel catheter in this case gets into the bladder inadequately lubricated and causes damage to the urethra.


Catheters with a hydrophilic layer on the surface reduce the possibility of complications related to intermittent catheterization, such as urinary tract infections caused by contamination and discomfort.