I think it may be zopiclone after 4 nights consecutive.  It is a side effect noted in the monogrpah of the drug. I am super stressed because Billy is not eating anymore. We may go buy him his old food though he was itchy on it. I hate the health problems CONSTANT and super expensive of this dog. What a lemon! we dont have another 1K to put on him when his teeth will have to be pulled because they are so bad. He put us in debt 7K!! in 3 months after we got him! I am so stressed out because he wont eat anything since yesterday. Though he has stopped chewing his paws which the vet would have said was allergies so thats why I changed his food. Now his poop is water afetr 7 days on it and he stopped eating. I hate his bad health!