HELP..My Cat's bowel stinks the house up badly??

what should I do about my cat using his litter..we have tried ever litter brand on the market even deoderizer..it doesn't work..His bowel is so foul it makes my and mother's stomach churn not turn churn...He's 6 months now..do you know what I can give him for his system..I mean I know when cats go they go..but this kitten that I got..Saddam won't need a nuclear missle..I would gladly give my kitten and just lite up a lighter