Nope, that's okay as long as it's not in too cold an area. If the ambient (room) temps are low, you might want to put it on top of a couple inches of heating pad. Chances are that he'll be more comfortable with it after a bath or three and will actually head for the water once he can feel it on his tail. He will absorb some of the water through his skin and should start to feel better in just a few days, but my vet told me to do it for a couple of weeks.