A Reddit.com user says the following: “Cat started peeing in the sink – don’t know if I should be impressed or concerned”. I’d be concerned even if the cat looks healthy and is behaving normally and pooping in the litter tray. This points to cystitis, an inflammation of the bladder due to a bacterial infection. It affects male cats more than females. Cats with cystitis have a strong desire to pee and grab whatever place they can find and don’t pee much and sometimes pee bloody urine due to the infection.
It is almost as if they are doing their best to be helpful by peeing in the sink which is why the owner asks if she should be impressed. Cystitis is often idiopathic – no obvious cause – and exacerbated by stress which is commonly caused by being alone for long periods (separation anxiety).
If it is idiopathic cystitis, it can be cured with antibiotics, but the underlying cause needs to be assessed and removed. I shouldn’t be too difficult to work out the cause of the stress.
The main reason why I know so much about idiopathic cystitis is because many years ago it happened to my female cat because she was a full-time indoor cat and I was a full-time working solicitor. I became a locum solicitor which meant I was freelance and therefore able to choose when to work and for how long to a certain extent which helped to solve the problem.
Although I have a page (see below) on a home treatment for cystitis, it would be wise to go to the vet to check out for other possible illnesses.
Dr Bruce Fogle says this about another cause of cystitis in his book: Complete Cat Care:
“Some cats urinate more frequently often in strange places such as bathtubs, sinks or even frying pans because of a form of cystitis that is related to neurotransmitter chemicals in the brain.” It is more common in indoor cats and “it needs medical and dietary management”.
Cranberry extract can help dogs with cystitis, but it may be less effective in cats.
Below are some pages on the urinary tract.