Last night, you were looking forward to lounging on the sofa with your cat curled warmly against you. But your kitty was far from relaxed, going back and forth to the litter box, excessively licking, even meowing at unexpected times. This morning, he peed outside his litter box – something he hasn't done in years. Is he bored? Stressed out? Sick?

When your otherwise trained feline suddenly starts exhibiting odd litter box behavior, it can be difficult to know if it's a behavioral issue, or if there's a medical cause behind it. We turned to Big Heart Pet Brands' in-house veterinarian, Dr. Leslie, to find out what's behind urinary troubles in cats.

Q: Should I bring my cat to the vet any time he exhibits strange litter box behavior?

Dr. Leslie: Because there are a number of causes of lower urinary tract disease, consulting your veterinarian is important. Some causes of abnormal bathroom behavior in cats can be stressors, such as moving to a new house, new people, new pets or other illnesses. Diabetes, kidney disease, hyperthyroidism and osteoarthritis can also be underlying causes of unusual urinary behavior. Your veterinarian will run some diagnostic tests to understand the cause and to help advise a plan to get back on track.

Q: What urinary problems affect cats?

Dr. Leslie: Urinary tract infections (UTIs) are very uncommon in cats. A positive urine culture is really the only way to know if your cat has an infection. More common is feline lower urinary tract disease (FLUTD), which refers to any of the complex disorders that result in abnormal urination or urinary behavior.

woman laying on a white bed with her white cat

Q: How dangerous are these conditions?

Dr. Leslie: Though uncommon, true UTIs can be associated with kidney infections, which can make cats extremely ill and can lead to sudden kidney failure. If not treated quickly, this can be fatal.

FLUTD may result in the accumulation and even concretion of cells, mucous and crystals in the bladder and urethra. If this were to occur in the urethra, your cat wouldn't be able to void urine, leading to potentially serious problems. A urethra obstruction is a medical emergency and your cat should be seen immediately — even in the middle of the night! Indoor, neutered, male cats are at higher risk for urethral obstructions; it is rare in female cats.

Q: What can I do to maintain my cat's urinary tract health, especially as he or she ages?

Dr. Leslie: Water, water, water and water! To increase water in the overall diet, try these techniques: provide multiple water bowls around the house that are wide enough so whiskers don't touch the bowl, add a water fountain or add more high-moisture wet cat food, such as from a can or pouch.

Signs of a urinary tract issue can be distressing for cats and parents alike. But check out the 4 signs of a happy cat, and you'll know when everything is a-OK.