Today, for some strange reason, smith has started licking the walls in the flat. He seems to prefer just 3 areas, and I'm worried about him ingesting some dangerous chemical - yeah, they were painted over 2 years ago, but I certainly wouldn't like a tongue full of dried emulsion!

Why is he doing this?

and

Should I worry? I can't stop him doing it when I'm out, but...

You could get a kitty cone for when you leave so he can't physically reach the wall. I dunno why he's doing it though. My cat, after living in the apartment for six months, suddenly took a liking to my roomie's speakers. The only thing I could guess is that something's been spilled on it? Eventually Azuri (my cat) stopped licking it, but it took her two days to get out of that faze.

Not sure if the link below will help.

Excessive licking

Could be your cat is bored or perhaps a bit stressed? Try a couple of plug in Feliway Diffusers.

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Kaz

For kittens, joy is for the asking and smiles are for the giving

Hello!

There can be several reasons for this behaviour...

Behavioural, Pica, stress or anemia (look into all of these).

I have a cat that likes to lick furniture, floors (gotta really watch which products I use), soap and my skin . Had all the tests done as I suspected anemia, but no it wasn't.... Its just something he does, when he can smell certain substances he is attracted to. 9 years down the line he still does it, but find he is attracted to surfaces treated with anything with ethanol glycol/propylene glycol which are members of the antifreeze family. REALLY toxic to cats, but they are attracted to the sweet taste/smell.

Baby wipes, body lotions, shampoos, furniture polish and cleaning products (the list is endless) contain this, so I have to be very careful what I have used when he wants to 'lick' ....

Maybe you have cleaned your walls with a product, your cat is attracted to?

I think an elizabethan collar would be a bit cruel to put on a cat, while owners are out. Especially if turned out to be stress related, the collar would cause more stress imo. And cat would still be able to lick walls...

Perhaps you could spray the particular area of wall he likes to lick with Bitter Apple Spray or a weak vinegar solution - though this obviously will probably leave your room smelling like a chippy!

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Kaz

For kittens, joy is for the asking and smiles are for the giving

Ha! No, it's a new build (less than 3 years old), and they haven't been 'cleaned', as such.

Two earlier points - we suspect that when we got him he was maybe only 4 or 5 weeks old, rather than 6 as the owner said. So maybe he did leave his mum too early.
Also, he is on his own quite a lot each day - but I try not to leave him for too long at a time. At least until he's neutered.
He's been doing it again this morning. And he bit me when I was stroking him. Grrr!

Try spraying some orange juice lightly on the walls. My cat HATES anything citrus-y!