Is washing your catheter a good idea? Ask a nurse that has been in the industry and she/he may talk to you about when we as a society saw washing catheters and needles as an appropriate practice.
However, as we know needles carry unwanted microorganisms that we can’t remove. The same is said about washing catheters. More importantly a sterile environment to wash them in is extremely difficult to establish. It takes only one microorganism to multiply on your product to result in a urinary tract infection.
In this link from WEBMD they recognize that the average kitchen sink is dirtier than your toilet. https://www.webmd.com/women/features/places-germs-hide#1
The cost for hospital treatment of a catheter associated urinary tract infection compared to a catheter itself is drastic. Consider your health next time you think of washing your catheter.