For older cats, one study showed that
87% of all male cats stop spraying after castration
78% stop immediately
9% stop in a few months
13% keep spraying
Another study showed that 77% of cats reduced or stopped spraying within six months of being neutered or spayed.
Anti anxiety drugs are available from your vet which may be useful in preventing your cat from spraying. Discuss the use of drugs with your vet.
Clomicalm and valium are drugs available only from Veterinarians and are used for treating spraying problems in cats. Some people report that their cats lose their personality and become zombies when on anti anxiety drugs.
As far as surgery goes, neutering should help. This could be a behavioral issue. A urinalysis should be performed to rule out medical problems. Treatment is aimed at decreasing the motivation for spraying. It has been shown that spraying may be reduced in some cases by reviewing and improving litterbox hygiene. Ideally the minimum number of litter boxes should equal the number of cats plus one, the litter should be cleaned daily and changed at least once a week, and proper odor neutralizing products should be used on any sprayed sites.
If the problem is due to social interactions inside the home, it may be necessary to determine which cats do not get along. Keep these cats in separate parts of the home with their own litter and sleeping areas. Reintroduction of the cats may be possible when they are properly supervised. Allowing the cats together for positive experiences such as feeding, treats and play sessions, helps them to get used to the presence of each other, at least on a limited basis. However, when numbers of cats in a home reach 7-10 cats you will often have spraying and marking.
Since the “purpose” of spraying is to mark an area with urine odor, it is not surprising that as the odor is cleaned up, the cat wants to refresh the area with more urine. Cleaning alone does little to reduce spraying. Cats that mark in one or two particular areas may cease if the function of the area is changed. It is unlikely that cats will spray in their feeding, sleeping or scratching areas. It has also been shown that cats that mark an area with cheek glands are less likely to mark in other ways such as with urine. In fact it might be said that cats that use their cheek glands are marking in a more calm, familiar manner while those that urine mark are doing so in a more reactive, anxious manner. A commercial product containing synthetic facial pheromone (Feliway) has proven to be an effective way of reducing urine marking in some cats. When sprayed on areas where cats have sprayed urine or on those areas where it can be anticipated that the cat is likely to spray, it may decrease the likelihood of additional spraying in those areas. The scent of the pheromone may stimulate cheek gland marking (bunting), rather than urine spraying.
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