It's important to keep in mind that unpleasant litter box odor can sometimes be an indication of underlying health issues in your cat, such as kidney problems or urinary tract infections. Therefore, if you observe a sudden increase in litter box odor or any changes in your cat's litter box behavior, it's crucial to seek advice from your veterinarian. They can help identify and address any underlying health concerns, which can improve your cat's overall well-being.