Well..... Here's the thing: from the sound of his problems I don't think Feliway will work. And it is very expensive.
Junior's "issues" sound so much like Jeddie's. I have had Jeddie about 2-1/2 years. When I got him he was in sad shape (thin, bedraggled, depressed at suddenly being in a strange place with strange cats and a, um, stranger). He chewed off all his belly fur. He bit at himself, he was clingy. And peed outside the box. I thought as time went by and he knew he had a safe and loving home he would calm down and stop the OCD behavior and inappropriate peeing. I tried Feliway and another similar product, and Rescue Remedy. None of them worked even the slightest bit.
I ended up having to rip up carpet in the second bedroom, bleach and seal the subflooring and put down tiles. He started peeing on my front door. And he peed on the doors at the house in MI where I take the cats for vacation. To be honest, this was a deal breaker for me. He was a loving cat, but I could not have my home and processions peed on.
Several people here suggested prozac. I resisted because I didn't' want a zombie cat and, in general, I don't like treating things with chemicals. After 8 months I had to do something and a friend gave me a few prozac to try. It was like flipping a switch. Immediately the peeing stopped. I mean, the very next day. The other benefit was that he relaxed. He wasn't high-strung, just anxious. I think his true personality came out. He was the same cat only like a cat that has let out a huge sigh. He had kept himself an outsider, but about 14 months ago he started interacting with the other cats more and is now a cuddle buddy with Beau (they are sleeping together in a chair right now. Jed has his head pressed into Beau's stomach).
I tried to ween him off it at about 6 months, but when I got to every 3rd day he started peeing on the door again. He has been on 1/4 tab (10 mg) sid for about 20 months now. It's the generic, fluoxetine, and it's pretty cheap. He has peed outside the box maybe 3-4 times over that time (other than when I tried to ween him off). I can deal with that. I could not deal with it on a daily bases.
My vet had never used it before, but I said that I knew people who used it with their cats with success and she said we could try it. I never saw a change in his BGs from it in either direction - not that I could notice, at least. If Junior is truly stressed I suppose it could lower his stress and, therefore, lower his BGs, but that would just be a bonus to, hopefully, having the other issues cleared up.
Oh, and I use a piece of pill pocket to wrap around it before pilling Jeddie. For a while he would eat it himself in the pill pocket, but that only lasted a few months. If he tastes the pill (easy to do with the cut edges) he starts foaming at the mouth. It must taste really nasty. So wraping it in the pill pocket helps. I suppose you could use liver sausage too, but that is messier.
