World’s Best Cat Litter® Health Check-In™ Boosters™ litter additive uses patented technology that turns blue when there is blood in a cat’s urine (hematuria) and stays white when your cat is healthy. Developed in collaboration with veterinary universities, it provides a very reliable and precise indicator of early urinary tract issues. Vet-approved and clinically tested, meet the safe and reliable way to monitor your feline friend’s health.

The easy-to-read health monitoring formula changes color in seconds and has a long-lasting vibrant color for at least 48 hours, so you can check when it’s convenient for you. Checking daily is a great way to help keep track of your cat’s health.