Cat is pooping and peeing around the house

Question
This past summer we left for a vacation and our neighbor took care of our cat while we were away.  The neighbor would come in and check on our cat only to find that she had not touched her litter box.  The cat had pooped in various spots all over the house. When we came home, we figured that the cat had just been angry and would go back to her litter box as normal again.  Three months later she countinues to poop and pee around the house.  Very rarely will she go in the box.  She does go outside occasionally, but every couple of days she goes inside.  She has LOTS of opportunities to go outside or use her box, so it is not an accident.  Please help we are running out of carpet cleaner.  

Answer
I would highly recommend that you take her to the vet for an examination to rule out any medical problems.  A stool sample and a urine sample should be checked, and sometimes blood tests must be done to check kidney/liver and rule out diabetes.  She may very well have a medical problem that is causing her to do this and not out of spite.

In the meantime, you should ditch the old litter boxes and get new ones.  She may be associating the old litter boxes with pain or anxiety and stress since you had left her alone.  This sounds like a litter box aversion since she will not use them.  The rule of thumb is one more litter box than the number of cats in the house.   Scoop the boxes every day and totally clean them with hot, soapy, water every 1-2 weeks (never use chemicals as they can react with the ammonia in the cat's urine and produce a noxious gas).  Make sure to praise her when she uses the litter box and NEVER PUNISH HER for not using the box or you will just worsen the situation.  Also, make sure she is getting some physical play time with you for at least 20 minutes a day which will help reduce her stress.

I would highly recommend CAT ATTRACT which is a special litter designed to draw cats back to the box  www.preciouscat.com

And lastly, I would suggest that you get FELIWAY/Comfort Zone diffusers for the house to help ease the stress and anxiety.