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There are many reasons for cats to urinate around the house. Some may have litterbox avoidance issues or not like the box or the litter; if there is an underlying medical condition like a urinary tract or bladder infection, it causes discomfort when they eliminate and they come to associate the place of elimination with this discomfort, so they'd rather go anywhere else.
Use an uncovered litterbox that's big enough for your cat to turn around in, without any problem and use a litter that is unscented. You can add 'Cat Attract,' a clumping kitty litter that contains herbal attractants and encourages use of the litterbox, to your cat's regular litter. You can find Cat Attract in most pet supply stores or order it online.
It's important to know if your cat is male or female, because if a male should have a UTI, this can quickly turn into a urethral blockage, where he can't urinate at all, and that is a medical emergency.
In females, if she's not spayed, this can also result in inappropriate urination, especially when she's in heat. Both genders can urinate in areas to 'mark' territory if they feel threatened or smell another cat outside; this is instinctive behavior. If this might be the case, you can lightly spray Feliway (information, below) around window frames, window sills and doors leading to the outside, but, allow to dry fully, about 30 minutes, before allowing your cat to access the sprayed area.
The first thing we do, when a cat is urinating inappropriately, is recommend a vet visit for a hands on exam and urinalysis/urine culture. If a medical condition is ruled out (hopefully), then, we can treat this as a behavioral-only problem.
Many cats urinate outside the box due to stress. Stress in cats is different than stress in humans. Since cats are creatures of habit, any minor change could cause stress/anxiety in a cat. for example, if she heard a loud noise outside or in the house, if you had a change in your hours or routine, if you had visitors (human and pet), got new furniture, changed the arrangement of furniture, got new carpet, painted, adding a ceiling fan, etc., this can cause a cat to be stressed.
Make sure the box (or boxes--you should have 2 boxes for 1 cat, located in different areas of the house) is placed in a quiet, low-traffic area, away from any noisy appliances.
Feliway, a cat-calming pheromone is available in a plug-in diffuser and a spray and is well-recommended for helping to ease stress/anxiety and therefore, inappropriate elimination. The plug in resembles a plug in air freshener, but has no scent to humans. It emits calming pheromones only detectable by cats. You can find Feliway in major pet supplies stores, your vet may sell it, or it can be ordered online. Here is more information:
Also, keep all boxes clean, by scooping as soon as you notice a 'deposit' and clean it thoroughly with mild soap and warm water, at least once a week. The plastic of the box absorbs odors and retains them and many cats are fussy and don't like a smelly box (who would?).
In addition, it's very important that you clean the areas she's soiled, with an enzyme-based cleaner made for organic (pet) stains/odors. You can find these in pet supply stores, home improvement stores and places like Walmart. Nature's Miracle, Odor Mute, Urine Off and Zero Odor are well-recommended, but you will see a big selection in your pet store; just make sure it says 'enzyme-based' or 'enzyme-action' on the bottle. After you clean the areas thoroughly, wait for them to dry completely and then spray a little bit of Feliway over the spot, let that dry completely (as mentioned above, about 30 minutes), before allowing your kitty access to the area. This will make your cat think s/he has already 'marked' there.
If all is well, medically, you have cleaned all soiled areas well, are using Feliway to help dispel any stress and your kitty continues to urinate around the house, discuss a prescription medication called Clomicalm (and there are many others) that will help in this situation. Here is more information:
I always prefer to recommend a prescription medication as a last resort.
I hope you find my answer helpful and things will improve with your kitty, very soon!
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