Are there any medical reasons why a dog might become obsessed with licking all of the sudden? What about behaviorial reasons? Delia has never been a "licker". Maybe a quick one when she says hello, but that's it. However, in the last month that's completely changed. She's crazy about it now and will try to lick you any chance she gets. I have to kick her out of bed now because she tries to lick my arm all night long otherwise Nothing else really seems out of place, though. Her temperment and activity level are unchanged. I mean I've known several dogs like that in the past, but just think it's weird that it just seemed to be a sudden, abrupt change in behavior.