My boyfriend has a four year old Great Dane that has severe gas. He doesn't like to let him in the house because he stinks the whole thing up rather quickly. He was feeding him better dog food but just switched back to the cheap stuff which I am working on him about. Can you give a dog acidopholus? Would that even help? Other than changing his dog food, any other suggestions. Oh and he is really skinny- you can see his spine and ribs. He free feeds him. And the dog throws up on occasion.
I would have him checked out by a vet, just to make sure there is not something else going on. Then change him to a high quality diet, such as Merrick, Innova, Call of the wild, etc. See if that helps, as far as somthing to give, I have no ideas.
If he is free fed and still underweight you definately need to get him to a vet asap. The throwing up in a Great Dane can be a sign of a major gastrointestinal problem. Also its a horrible idea to feed a Great Dane cheap grain-based food because of the skeletal problems they can have. They need to be kept on a high quality large breed adult formula and fed at least four times daily to minimize the chance of bloat which is one of the leading causes of death in the breed.