I have a 4 year old Lhasa Apso and we have had him for around 4 months and he constantly licks everything. He licks the lounge, the carpet, the vinyl floors. His favourite is pillows that people have been sleeping on.
I have found that licking can be caused by several things- my hound licks the floor and linens when he needs to vomit- does your dog eat grass when he goes outside? Trevor would literally clean the floor and then if I put him outside he would eat grass, leaves, branches, anything he could chew and then vomit. I have seen licking also (though usually skin) in an effort to get salt if the dog is dehydrated. It could also be a nervous habit if there is no rhyme or reason to the licking. hope this helps..
My mother has a Lhaspa Poo and she constantly licks also. It could very well be a problem with the nervous system, however if the dog is licking the floor and all of that, perhaps there was something that was spilt on the floor, linen, or a smell that they like or anything really and the dog is trying to get a taste of it or perhaps missing someone. I would suggest getting a spray that's called Bitter Apple. I've used it a few times when my dog was eating the inside of my couch. but then she stopped. Also, you can also mix vinegar and water and spray it on stuff...that may help. but with the dog licking an arm, the other person is right, they must lack salt. Try putting some salt in their food.
hope this helps. :)
Thank you very much for your great ideas. I will definately try them and I will cross my fingers.