Cat urine odours are notoriously difficult to remove. Male cats contains hormones which make the urine smell much stronger than that of females or neutered males. These hormones serve a purpose, to enable the male cat to mark his territory. Male cats exhibit this behaviour to attracting females and deterring any possible competing males.
Cat urine smells the moment after she urinates or sprays. The longer that urine sits, the worse the stench becomes. The main odor-causing culprits, urea. Bacteria have the ability to hydrolyze the urea, which releases ammonia. It is also part of why cat pee glows under a black light. Most cleaning products easily take care of urea , but detergents and soaps will not remove uric acid. Uric acid crystallizes and bonds to porous surfaces, such as carpet, fibres, which makes is very difficult to remove. Often, we think that urine is gone once they dry up and crystallised. The truth is cat’s sensitive noses can smell the uric acid and will return to the same spot to urinate.
On a humid day, the odour is released when the crystals absorb surrounding moisture. To remove uric acid, use a solution specifically formulated to remove cat urine odours. Using an enzyme cleaner breaks up the crystals in the uric acid to permanently remove the smell.
Most enzymatic cleaners require several applications to fully remove uric acid, especially if the stain is old. While enzyme cleaners come in a spray bottle, spraying a light coat over the stain would not do much. For best results, remove the sprayer and douse the spot liberally. Allow the enzyme cleaner to air dry, letting the cleaner sit for 10 to 15 minutes. The drying time break down the uric acid salts, allowing the resulting gases to evaporate. After which blot up as much of it as possible with a clean cloth. Remember not to use ammonia or an ammonia-based product to try to remove cat urine. Cat urine contains ammonia, cleaning urine with an ammonia product will just encourage your cat to return to the area.