Why Does My Cat Lie in the Litter Box?

If you have recently adopted your cat, he may spend a lot of time hanging out in the litter box because he is unsure of his surroundings and feels safe in there, especially in an enclosed box. While this may seem unacceptable to humans, the litter box smells like your cat and the scent of his urine; cats actually mark their territory with their urine and its scent can sometimes be comforting to an anxious cat. Your cat should begin to explore his new home after a few days, but if he continues to spend time in the litter box, provide him with a separate box that contains a blanket instead of cat litter. This way, he has a spot to cuddle and sleep in as his refuge.

A cat who is under stress from the addition of a new animal, such as a second cat, may sit in the litter box to claim it as his own and prevent the other cat from using the box. The cat may also stay in the litter box for safety if he feels threatened by another cat or dog. Provide multiple cats with a litter box for each cat plus one extra to prevent territorial issues involving litter box guarding, recommends the American Society for the Prevention of Cruelty to Animals. If you have a dog, place your cat's litter box in an area that your cat can easily get to without being bothered by your dog, or set up a special room for him that your dog can't access. A few sprays of a synthetic cat pheromone or a pheromone diffuser can also put your cat at ease, reducing his desire to hide and lie in the litter box. In serious cases, you may want to consult with your vet about the use of an anti-anxiety medication to curb your cat's desire to hide in the litter box.

A cat who lies in the litter box may do so because he is unable to urinate properly due to a condition called dysuria, which may prompt him to stay in the litter box to continually try. Dysuria results in painful urination, blood in the urine, the frequent urge to urinate and unproductive urination. There are several causes for this condition, including a urinary tract infection, the presence of crystals in the bladder and tumors in the bladder or urethra, according to PetPlace. Because these conditions give your cat the urge to urinate, but he is unable to, he may lie in the box to continue to try. They also cause fatigue, weakness and nausea; this is part of the reason why you find him lying in the litter box—he may be too exhausted to move.

Urinary tract infections are caused by the presence of bacteria in the bladder and cause pain when the cat urinates. When a cat's urine is too acidic, calcium oxalate crystals in the kidneys or bladder may form; when it's too alkaline, struvite crystals form. These crystals not only irritate the bladder, causing an infection, but can lead to a blocked urethra. A cat with a blocked urethra cannot urinate, leading to a buildup of potassium in the body. This is medical emergency and can result in kidney or heart failure if not treated within 24 hours, according to the 2nchance.info website. Visit your veterinarian for a proper diagnosis and treatment.

Another possible cause of a cat lying in a litter box is feline interstitial cystitis, a neurological condition that increases your cat's need to urinate more frequently. It is a painful condition that is also a medical emergency, according to the ASPCA.

Chronic diarrhea or gastrointestinal upset may cause your cat to lie in the litter box due to the constant urge to defecate. A number of intestinal conditions, including internal parasite infestation, colitis and megacolon can cause diarrhea, according to Cat Channel. If you've recently changed your cat's diet, this could also be the cause of stomach upset that propels your cat to lie in the litter box. An exam by a veterinarian can determine if there is a medical cause for your cat's behavior.

Another issue that could lead to your cat sitting in the litter box is pain from an injury or arthritis. Elderly cats may have trouble climbing into and out of the litter box and may be reluctant to leave the box once inside because of the pain involved. Switch to a litter box with low sides that your cat can navigate without pain. Place the box in a spot that is easy for him to access, perhaps close to a favorite napping spot.