How do you get the smell out of the couch?

My Tater got into a spot on the couch last night. I know the drill, but the smell is coming back even after I wiped it. What actually works to kill the odor permanently without using harsh chemicals?

Use an enzymatic cleaner. Regular soap or vinegar won't break down the proteins in the urine, so the smell lingers and the cat smells it too. I keep a bottle of the stuff in my closet specifically for this.

I've seen people say vinegar works. Is that true? I don't want to ruin the fabric.

Also, does it matter if the stain is old? I think this spot has had some history.

Please do not use ammonia. It smells like urine to the cat and will encourage them to go there again. I learned that the hard way with my Tux years ago.

Good point about the ammonia. I saw a thread about this recently, ammonia and re-marking behavior. It makes sense. But for the actual cleaning, what's the best method for fabric?

I found this older discussion where people argued about whether baking soda helps or just masks the smell. enzymatic cleaner recommendations. I think I need to look up specific brands.

Also, should I worry about medical issues? Tater is healthy, but just in case. medical causes of inappropriate urination. And for old stains, I saw removing old set-in urine odors. I'll try the enzyme stuff first.