spraying cat

Question
Hi Jessica
I just sent you an e-mail regarding our spraying cat,Milo.
I forgot to mention 1 very important thing.That he adopted us.He was an outdoor cat that rarely went home.We know where he lived and the owner has indicated that he did'nt want to be there.If they tried to keep him in he would hiss and even scratch them as well as destroy furniture.We have never seen any sign of that type of behavior from him.He's very affectionate with us.
He showed up about 2 years ago and became best friends with our cat.They are inseparable.
We have a cat door and he just started coming in.We started closing the door but he would just curl up on a patio chair and wait for us.Gradually he made us his and we in turn made him ours.
I think that may be why he sprayed at first,to mark what he wanted to be his.
But it now is and he is getting worse.Don't know what to do!!
Anyways I thought that I should tell you so you see the whole picture.
Thanks again   Laura

Answer
Sorry, I read this after answering the first one.

One additional thing I would mention is, how did you use the Feliway?  Did you spray it right over areas he's sprayed?  If not, you might want to try that.  You clean the area with rubbing alcohol, then rinse with water, and apply Feliway several times a day directly to the soiled area.

Also, not sure how long you used the Feliway, but there is evidence that it increases in efficacy the longer it's used, often requiring a few months' of use before it reaches its full effect.

If you did that and it didn't work, I would suggest trying an enzymatic cleaner if you haven't gone with that yet.  This uses enzymes to break down the fat molecules in cat urine, which make stains stick.  Then you can remove the stain fully and not have him still smelling the scent.  Nature's Miracle is an enzymatic cleaner sold at pet stores.  I personally use Greased Lightning Orange Blast, available in the auto section at most stores, which uses the enzymes in orange oil.  These shouldn't be used with Feliway, though, because the scents of the cleaners interfere with the effect of Feliway.

One other thing that may help in males who are marking territorially is megestrol acetate, a synthetic female hormone.  It can be given as an injection or in pill form.  Typically, improvement will be evident within a couple weeks if the cat is going to respond to this treatment.  However, the drug should not be used any longer than 2 months, because diabetes and mammary cancer, even in males, are very common serious complications if the drug is used longterm.  I had one cat who was on it for several years, before I knew better (the vet was VERY old school).  He died of mammary cancer at 9 years old - the only case of mammary cancer in a male that my new vet had ever seen.  So unless euthanasia is the only alternative, I would not use megestrol acetate for longer than 2 months.