This is my five year old ex Dogs Trust rescue mongrel terrier. Got him at 18 months, ex Irish street stray. He always licked, I thought he could be trained out of it. He can't. I can stop him and do, but cannot stop him starting ( if you get the difference ). Within the last twelve months his progressive blindness due to genetic condition PRA was confirmed. The obsessive licking predated this and continues at same rate. Someone recently suggested the licking may be a retained juvenile trait, possibly indicating some brain damage, the equivalent of a human learning difficulty. He licks as though hypnotised, on and on until interrupted. He licks anything; people, furniture, carpets, the cat, his bedding....help!