My baby boy Nahla is just over two years old. about 2 months ago he started exibiting breathing issues that gradually got worse after spending about 1000 dollars at the vet with no answers, no definitive diagnosis.. He was and still is being treated for asthma.he has been on several steroids, antibiotics, and is now using albuterol for breathing treatments. I have recently noticed that when he comes up from the basement, which is where I keep my litter box. I have noticed that when he comes upstairs after using the litter box he is more apt to have an attack, and has very labored breathing. Any stayhe has had at the vet he has never exhibited any breathing trouble.I live in a very small town the only option for cat litter is Walmart, I know they carry severalmore natural brands, I also know to stay away from pine.. Is there anything that anybody would suggest?