Eliminating or reducing the odor of cat urine can be tough. Washing the area with carbonated soda water or with soapy water has been somewhat effective. As a deterrent, you can use vinegar, moth repellent spray or mouthwash.
The most effect method is to use one of the variety of over-the-counter products specifically made to neutralize and break down the source of the urine odors. Some of these products include Zero Odor, Cat-Off, Nature's Miracle, F.O.N., Odorban, Odornil, Nilodor and Anti Icky Poo.
Any product that contains ammonia should be avoided, since the odor of ammonia is similar to the odor of urine.
After cleaning the area, placing a litter box or even small food bowls over the affected area may also help to deter the cat from future house soiling episodes.
For more information on reducing cat urine odor, please click on Reducing Cat Urine Odor