An animal's inability to tell you when they aren't feeling well is one of the hardest parts of pet parenthood. Even when they're showing symptoms, you can't just ask them what's wrong. (Well, you can—just don't expect an answer.) Pretty Litter is a subscription-based litter service that wants to help when it comes to cats.
A litter box is a necessary part of coexisting with a cat, and Pretty Litter claims its crystals change color when your cat might have an illness, making it easy to tell when something might be wrong. The company's founder, Daniel Rotman, lost a beloved cat that showed no obvious signs of sickness. This litter is his solution to help monitor a cat's health at home, to hopefully prevent what happened to him from happening to other pet owners.
I—with the help of my two cats, Huxley and Eely-Rue—put Pretty Litter's crystals to the test for several weeks. I also spoke to veterinarians, cat behaviorists, and Pretty Litter customers to figure out whether the crystals accurately do their job. One thing I need to say before jumping into my experience is that Pretty Litter should be used only in addition to regular vet checkups. It is not a replacement for veterinary care.
Pretty Litter's crystals change color based on the pH level of your cat's urine. Normal pH urine will turn the crystals a yellow or olive green; a high pH, which could mean a urinary tract infection (UTI), makes the crystals turn blue; and low urinary pH turns them dark orange, and it could mean metabolic acidosis and kidney tubular acidosis, which can lead to kidney stones. Blood in the urine shows up as red, as expected, and could mean bladder inflammation, bladder stones, or a UTI.
It can be complicated to determine where on the scale the color falls, as it can look like it's somewhere in the middle. To test for high acidity (low urinary pH), I used vinegar. It turned the crystals a yellowish-orange, which could have been the mark of low urinary pH but could also have been the yellowish color of normal urine pH. After looking through my cats' used litter, I saw a similar color and couldn't quite determine its place between normal and low pH. I made an appointment with my vet to have both my cats looked at, just to be safe, and the doctor said they weren't showing any issues.
In my research, I found several Pretty Litter customers talking about false positives on Reddit. Their cats' litter crystals turned blue, but expensive vet visits concluded there was nothing abnormal. It's not all bad. I spoke to one customer on Twitter who regularly fosters cats and has been using Pretty Litter for around two years. She said when the color changed with a new batch of kittens, she took them to the vet and found they had worms. Another customer said the crystals turned blue, detecting a UTI that was later confirmed by a vet, who was impressed the litter caught it so early.
But there's also the possibility of false negatives. My friend's sister has a cat with a history of frequent UTIs, but the litter never changed color. When she called the company, a customer representative suggested buying more litter and boxes, a solution that didn't really make sense to her. (She noted that customer service really pushed her to buy more litter when she called to cancel her subscription, too.)