How can I get old cat urine smell out of a mattress?

Question

When we went on a weekend trip a few months ago, I forgot to leave the door open to the cat boxes. So the kitties used our mattress as a replacement. When we got home we cleaned up as best as we could. We bought an enzyme cleaner and some febreeze. We were satisfied with our efforts and tried to continue to use the mattress.

However, a few days after cleaning, the smell of cat urine returned. The smell kept coming back after every cleaning so we decided to switch mattresses with an older one we had on a guest bed. It has been several months now and there is still a smell of cat urine that lingers on the mattress. We have kept the cats out of the guest bedroom so there have not been any additional accidents. We would like to get the smell out and buying a new mattress is not an option.

What else can we do?

Answer 1

I would suggest that you attempt a complete soak of the area. Also, keep in mind that there may be multiple areas, some large, some small. I understand this will be quite challenging for a mattress.

Please read the following for my reasoning, which is based on one company - but applies to all cleaners, enzymatic or not.

An enzymatic cleaner such as Kids 'n' Pets (I use) sells their product in a large non-spraying bottle, similar to the water bottles used for bike rides. Before their website received an overhaul, they used to have a FAQ page which included "Why does Kids'n'Pets come in a squirt bottle and not a spray bottle?" They explained that the common problem with pet-stain-cleaners was that customers never soaked the area as thoroughly as the urine originally did. Urinating directly onto a carpet (or mattress) allows liquid to travel deep down and outward. Customers often spray the surface based on the stain they see or think is there - which always allowed most of the urine (deeper under the carpet) to stay untreated. This leads to reoccurring smell, which leads to customers thinking the product doesn't work. They explained how the large opening squirt bottle encourages customers to actually completely soak the area. This way the product will work, and the customer will be happy. (It was not an expensive product) They promoted simply using your own squirt bottle for stains if you're sure they are surface-only. Unfortunately the product has grown in popularity; their website has gotten fancy; and I cannot find this information anymore. However, the logic is sound. People often just need to use more product.

Pick a product you're sure will work on urine, not just microbes. If it kills the microbes, but leaves urine in it's original "edible" state, more microbes will just move in later and make the smell again. Remember, it's not really the urine that smells, but the microbial action. You need something that will break down urine into a form that's not usable by the microbes which cause the smell.

I have used Kids'n'Pets for cat accidents including: food-based vomit, bile-based vomit (very very neon green stains) (a medical issue, now treated), feces smears (cat eats long human hair and freaks out during defecation); and very old, very stubborn grease oil (car/mechanic) stains in carpet. I have not used it on urine, but I originally chose it due to fabulous reviews (mostly about urine).

I would suggest buying an enzymatic cleaner in bulk from online and soaking as much of the mattress as you can. Try to sniff out all areas in advance and perhaps mark with a pen or marker. Use a black light (UV light) in the dark to find urine stains. Keep in mind that if you properly cleaned the surface - it may be impossible to find the stains visually. Try to remember where you cleaned before and soak those areas and/or use someone with an excellent nose.

Answer 2

I have used the get-rid-of-cat-urine-smell technique found at the following website with great success on both fresh and old stains on a mattress. All you need is vinegar, baking soda, hydrogen peroxide, dish soap, and water :) Good luck!! http://www.catsofaustralia.com/clean-cat-urine-mattress.htm

EDIT As requested (and rightfully so), here is the method that I found (and directly quote from the above website) - I have used it successfully twice on a number of stains each time. Darn cat...

Ingredients for the Cat Urine Recipe To Remove Odors & Stains from Mattress * Baking Soda * White Vinegar * Dishwashing Detergent (Dish Soap) * 3% Hydrogen Peroxide (10Vol)

Step 1 - If the urine is recent, blot up as much of it as you can using paper towels or a sponge. Apply plenty of pressure to reach the dampness deep down. Stand on the paper towels for more pressure if necessary. If you own a wet/dry vacuum cleaner extract as much of the moisture as you can. If the urine has dried proceed to step two.

Step 2 - Mix a solution of 50% vinegar and 50% water in a jug or other container. Pour a small amount of this solution over the area of cat urine. I used about 50mls. Then begin blotting (as described above to soak up this solution). Or use a wet/dry vacuum cleaner.

Step 3 - Sprinkle a good handful of baking soda over the area.

Step 4 - Mix a quarter of a cup of 3% (10 Vol) hydrogen peroxide with a teaspoon of dishwashing detergent and drizzle it over the area where you have sprinkled the baking powder and work it in using your fingers or use a brush. Allow fifteen minutes for the solution to work and then begin blotting again. (Don't use wet/dry vacuum at this stage, just blot)

Step 5 - The mattress must now be left to dry thoroughly. A good indication is when the baking soda feels completely dry. Next vacuum up the dry baking soda thoroughly. The baking soda absorbs the odor and urine. (Use a hard bristled brush to loosen up the baking soda if necessary) If you live in a sunny climate you may be able to put the mattress out in the sun to dry. You can also assist the drying process by using a fan or heater. Another idea from one of our readers is to use a hair dryer.

That's all there is to it. It's as easy as that.

Answer 3

I am a cat behaviorist and have been for more than 25 years. I am amazed to see myths still circulating on the web about using vinegar and hydrogen peroxide to clean urine. Those two substances, along with ammonia, are chemicals you should NEVER use. Why? An incomplete cleaning can encourage cats to return to the area and re-mark! Ammonia can degrade into what smells like urea. Vinegar and hydrogen peroxide only clean partially because they are unable to remove uric acid. You might not be able to smell it, but we're talking about a cat's sense of smell, not just yours.

Please stick to an enzyme cleaner especially formulated for cat urine.

Here is an article explaining the benefit of enzymatic cleaners and the problems with common household non-biotic cleaners such as vinegar and hydrogen peroxide. http://catcentric.org/care-and-health/removing-cat-urine/ Note that this article also heavily emphasizes a heavy soak with cleaner, not just a spray.

Answer 4

Get a steam cleaner, the kind that sprays out dirty water and sucks it back up. A Bissell or some other brand works well. Make sure it has a hose. They also sell smaller versions of this that only have a hose and nothing else. It will have two compartments, one for dirty water, one for clean. Once you have this (borrow or buy-worth the money though.. Seriously) open the windows in the room your about to clean the mattress in. If it's warm outside it will dry faster. Now, stand the mattress up on its side, upright. This will stop the water from going too far into the mattress and help it dry. Fill the clean water tank with a solution of 1/4 cup bleach and 2 tablespoons of liquid laundry detergent. The hotter the water the better. Now here comes the part that'd going to take a while but in the end you will be quite satisfied. Start at one top corner, working in roughly square foot patches, spraying the mattress with the solution and let it sit a minute. Then suck it back up, repeating as necessary until the water runs clear. Work your way to the bottom and make sure you take your time to suck out as much of the water as possible. You will be surprised at what comes out of the mattress. Dust mites, skin dirt and.. The pee. The bleach will kill germs and help it go back to its new color and the combination of the two (laundry detergent and bleach) will break down the dirt, bust up the pee and allow it to be suctioned out, killing any smell as it goes. I've had cats all my life and have seen this work before, as well as if there's anyone in the house with allergies it should help them. Just keep refilling the tank and emptying the old water (watch it's color even from seemingly clean spots to be effectively grossed out) and let it air dry. A fan helps but the open windows and sunlight should do the trick before bedtime if you start early enough in the morning. Expect to use between 7 and 9 tanks of water and spend about 3 hours. But I promise it works and will save your mattress. DO NOT DO THIS TO A MEMORY FOAM MATTRESS. It will not dry. Standard, normal, regular mattresses only.

Answer 5

I would also ditch the mattress and chalk it up to my careless decision.
I have used Nature's Miracle and the Febreeze products that spray on and are made especially for pets. These may be great, with repeated applications, for thin carpets but I doubt if you will ever get that odor out of something thick like a mattress. Even after you may think you have done the job, the first humid day will see that odor wafting out.

On the other hand, I've had a sofa that had a pretty bad odor to it. I had just purchased a new Dyson vacuum cleaner, and it took repeated tries over many days, but that renowned (ha) suction actually got rid of the smell. I have wall to wall industrial carpeting and that Dyson will pull it up off the floor a bit. When I first got it, for the first maybe 13 times I vacuumed, the floor looked clean, but it continued to pull debris that was deep seated in that carpet because my prior vacuums did such a lousy job.

Answer 6

Seriously, dump the mattress. All of these "formulas" never work, even the enzyme based ones don't completely get the job done. If you can't afford a new mattress, get an air mattress and keep the cats off of it. I've owned cats for 30+ years.

Answer 7

How to remove cat urine.

Once you find out a cat urine spot, you should:

Dry the urine from with paper towel and use the same to b the lot urine in rugs. Do not use cloth unless you're sure you won't need it again.

To clean the compounds that are not water-soluble, use enzyme cleaners which are the most powerful substance in term of cleaning cat urine. They are meant to destroy the uric acid into ammonia and carbon dioxide. You will notice that it will off gas afterward.

Use the best enzyme cleaner possible - inexpensive cleaners often require multiple uses before they remove the odor of cat urine.

Do not try to speed up the drying process after using an enzyme cleaner because you may stop the enzyme from dissipating of the ammonia and carbon dioxide.

When applying the cleaner; you should soak the target area to allow the enzymes to really do their job.

After leaving the cleaner on for approximately a quarter of an hour, blot it up, then let the spot dry naturally.

Although rugs are the usual areas where your cat may urinate, beds, sofas, and clothing can also be sullied. Use the same procedure on these as you did on your rug. Slipcovers and clothing should be washed separately after they have been treated with the enzyme cleaner. Spray marking will be found on a vertical surface such as a door frame or chair leg. I found this in this blog http://cathealthblog.ml

Answer 8

1 gallon of bleach 4 cups of laundry soap 10 gallons of water

I know this post is old but my kids are all really young and I have had to deal with pee soaked mattresses and sofas for the last 8 years.

If this happened to me. I would drag that thing outside and soak the entire mattress. Get it dry and stuff it in a bed bag (the kind you get when you are moving. The thick ones...)with about 4lbs of baking soda. I would duct tape that completely shut and that would be the mattress home until I was able to but a new bed. And/Or Me and my couch would be best friends for a while.

Answer 9

To get rid of cat urine smell most of the time: Rinse with water and dry in sunlight.

As for your mattress, too many layers. You will have to come up with a better solution then spending loads of money on a cleaner. Buy a new one