The fact my cat had a urinary tract problem causing her to pee in the
house, on the carpet of course, forced me to look into something to
get rid of the odors.
 One thing I quickly learned is that all products are NOT created
equal. Even when looking at an enzyme product I found a huge
discrepency. Most do not actually contain enzymes at all. They contain
bacteria that when stressed upon application create enzymes for a
limited period of time that "eat" urine etc. That is why they have a
delay in working and only last so long.
 I also found out that a lot of them have additives as well that are
not always good for your pets like isopropyl alchohol. I read a lot of
MSDS (Material Safety Data Sheets)and what I found was scary. The top
product on the market states it can cause liver and kidney damage!
 Most of the ones that actually contain enzymes only contain one or
two different enzymes limiting their effectiveness. I finaly found one
while talking to my sister who is a nurse It is used in hospitals etc
to deodorize things like colostomy bags. The US Postal Service uses it
to get rid of the smell after the mail is irradiated. It is so safe it
can be drank with no real problems. It is called Odor Away. So far the
only place I can find it is at www.cobblecreekconsulting.com . I used
it and it got rid of the smell almost on contact and so far, touch
wood, has not come back! It also got rid of the slight stain that was
there as well

Rob