Thought I'd pass on something that helps me out...if it's the same items of clothing or same area getting "annointed", the smell is very hard to get completely out. Even if we don't smell it, they can. What helps a bunch for me is adding 1 to 2 cups of white vinegar to the offending laundry. I also wipe down/wash the floor/carpet with a mixture of water and white vinegar. Cats hate the smell, plus it seems to eliminate the urine odor so they leave those things alone. Hope this helps you.

Jen