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Cat Pee Detective

Yeah, that should be my title! Do you know that cat urine phosphoresces (glows) in the dark if viewed under a black light (Wood's Light/UV light)?
If you fear your cat is urinating somewhere in your house, but can't find it, simply wait 'til evening, turn off the lights and grab a black light. Simply by sweeping the area with the light, you'll suddenly notice dribbles on a wall, puddles on the floor, or odd stains on the furniture. If you're not positive it's urine and think it's some other stain, you could be right! You might have to take a sniff of the area to be sure. Don't get too close though! Yecch!

I've use this method many times before and it works well. It also, sadly, works if you got to a hotel and run the black light over the bedding! "Other" stains will appear..the kind you don't want to know about. You might want to leave the black light home!

I have the black light but it doesn't seem to pick up anything on my floors. Works great on the fabrics.

But, umm... my cats are angels, I don't have a need for this :)

Is there something that you use for hardwood floor urine detection?

If they pee, it glows, whatever surface it's on! Yes, it works on hardwood floors. I only know because it happens here, um, too often.


-Covered in Cat Hair

I never see anything on the floors. I'll have to try late at night when it's really dark. That could be scary. Maybe my cats are just angels and only use the litter box :)

Tucker, when his pancreatitis is acting up, inappropriate elimination is his way of telling me it's time for meds. I guess that's better than having him suffer for weeks in pain. And he's nice enough to wait until I can see him doing it. Such a gentleman!

Thanks for the advice.

when i use the blacklight on the hardwood floors, all i see is thehardwood floor, it shows up as if under a white light.  what am i doing wrong?

Make sure it's dark.

You have to have the light close to the floor, like maybe a few inches at most. That may be the problem. You bring up a point that I'd like to talk about in more detail-how cats communicate with us. Inappropriate urination is often seen as the cat trying to "get revenge" on their owners, when in fact, as we know, it's them trying to tell us they are sick, unhappy, scared, etc.

I'm going to be Blogging about this issue because it just came up in our rescue group. Stay tuned.

-Covered in Cat Hair

Like I posted earlier. Tucker marks when his pancreatitis is flaring up.

My Lucy will mark only when she has a UTI.

I first learned of Tucker's diabetes when I brought him to the vet thinking he had a urinary tract infection, there was sugar in his urine and from there we learned about the pancreatitis and IBD.

I WANTED TO KNOW IF CATS HAVE A CERTIN PLACE THEY WOULD USUALLY PEE IN LIKE A CORNER OR SOMETHING BECAUSE I HAVE A SMELL OF CAT PEE BUT CANT FIND IT AND I TRIED THE BLACK LIGHT. was that easy. Cats can pee anywhere. You may have found the pee, but what did you use to clean it up? That's why you may still smell it. I rec'd works well and leaves a fresh scent. You're right on track with using a black light. That should show you the problem area, but you might need to look under things, behind furniture, on the sides of the sofa or on a wall. Really LOOK everywhere. I hope you can find it! Good luck!

was overwhelming. we got it toned down but I still smell it I'm going out and getting a black light tonight. What I really want to know is, does cat pee ever fad away or will people always smell it when they come over?

That is one tough smell to get rid of. I don't believe folks come here and smell it, but if you're still smelling it, odds are you MISSED a lot of places. That's what I find happens here. I think I know all the locations, then I find more by accident. You DO have to use the black light, but you also just have to "patrol" your home. That's what I have to do as well. The faster you clean it up, the better. I'd even repeat treat areas where it happens more often. I don't want to push one treatment or product but whatever you use let your cats tell you if it works-they will go over to an area that is not clean (even if you think it is) and spend time sniffing at it-or even flem (hold their mouth open) that is another telltale sign you missed a spot. Good luck!

Hi... i just found this stain on my sink and i have an older cat... it LOOKED like pee but I didnt smell anything... it had fur in it.. is it weird or normal that a cat would have fur in her pee?

I think some fur could have come off when the cat was in the sink and it just was in there with the pee. I don't think cats can urinate their fur. You can tell if it's pee if you use a black light to illuminate the sink which will make the cat pee glow.

Thank you Robin! I will definately have to buy a black light! I dont know why I havent after all these years of having cats around! I knew this and I never really bothered. But now since my baby is getting old, I get worried you know? I fear that day, when it comes. Shes a part of me now. Anyway, I will keep a closer eye on her and will get that black light! Is there a special kind that I should get? I like the ones they have on CSI because they are so portable. DO you have any suggestions in this area? Will a black light bulb work? You can use a bulb if you have just aren't as flexible in getting around with the cord.

Hi, I have a cat that is in heat, she seems in alot of pain and it hurts me to see her like this. Me and my husband were wondering if asprin is bad for cats. Would it help her?

I hope you see this msg..please DO NOT GIVE ASPIRIN TO YOUR CAT. Also, if she's in heat she should be SPAYED as soon as she's out of heat..if you have trouble finding a low cost clinic just email me and I'll find one for you. info @

My sister's cat is peeing everywhere but I'm the only one who notices, I just bought a black light so I can show my mom but the cat's urine does not show up under it. It also does not smell or stain the carpet. Is there a reason why it wouldn't? The cat is a young femal, un-spayed. She will not pee in her litterboxes, she has two and only uses one of them to poop.

I recently moved back home and that seems to be around when the cat started urinating, could it be a territorial thing? I came from an apartment with a male cat that had been spraying.

I'm looking into a local community program but it does still cost money which we don't have. She has never been to a vet and so will need all her shots as well. I live in North Central Massachusetts, if you know of or can recommend any programs I would appreciate it.

Contact the local low cost S/N clinic and tell them you can't afford to spay the cat. It's REALLY important that it is done-also the cat could have a urinary tract infection which is causing it to not use the litter pan. The Clinic may help you or let you know about a rescue group that can help you with the costs of the spay. No one wants intact cats running around so ask for help from local rescues and someone will help you. Make sure the pans are very clean, not in a busy area of the house, are not covered, are not using litter liners. Scoop EVERY DAY. Try using Cat Attract litter and see if that helps, too. Get the cat to the VET please!

I used a blacklight on a futon I know our cat peed on (I saw the wet mark on the cushion and the smell was... strong) but the spot did not show up under the blacklight.  I tried it at night with no other lights on in the house.  Might there be some other explanation?  Thanks!

Hi I just bought a UV Blacklight at Walmart (Rayovac flashlight) and I tried it on fresh and dried urine and vomit in the pitch black and it showed up nothing. I had an electric one from my sister in Canada and that thing was amazing. But it busted. So I brought the item back and ordered on line. i bought a hand held one for under $10.00 and it was worse then the Rayovac. Very dim and flimsy. I wish I could find another electric one. Have you had any luck with any peticular brand that actually will show up urineand puke. I have a 19 year old cat and 3 crazy dogs. I need a good light to find this boo boos. Also I tried a regular black light my landlord had but it was as useless and these two items. Ugh!! Any advice would be helpful. 

I haven't noticed cat pee in the litter box for like a week or more. I've sniffed all around and under furniture and can't smell or see anything. Where could my cat be peeing? 

About a month ago, my cat Milo was brought to the vet for peeing on my couches and they found traces of blood and a possible crystal trace but by the next day, and a antibiotic later, he was fine.
Today I smelled cat pee on the carpet under my couch but I can't tell if its old or new because it isn't actually wet. Is there a way to tell or should I just get Milo checked again?

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