On Monday, February 18, 2013 11:18:15 PM UTC-6, cat182 wrote:
Test results were all negative.

Blood results were normal.

UTI results were normal.

Vet suggested we take him to a Neurologist. That route is too

expensive.

Instead, we are going to try a few cheap alternatives.

The first thing we are going to do is change the litter to "Cat

Attract".

When I've used the Cat Attract litter, we've had good results.

You might consider using a Spirit Essence. We used an anxiety one for our middle cat and it did help: http://www.spiritessences.com

Lastly, ask your vet about putting him on a low-dose antidepressant. When my childhood cat got elderly (she lived to age 19), she urinated outside of the box regularly, among other cognitive symptoms like staring in the corner and meowing loudly for no apparent reason. My parents' vet prescribed an antidepressant and while it wasn't 100% effective it helped a lot--she lives two more years. Here is a good article about feline cognitive disorder: http://www.fabcats.org/owners/elderly/senility.html (see the section about management).