What to do if my dog starts acting weird?
If ever in doubt, call your vet. If there are any changes to your dog’s behavior, the first thing to do is get a vet evaluation before going to a trainer or behaviorist. Some behaviors are because of an illness.
What to do when your dog is acting strange?
If you notice that your dog is acting “strange”, showing behaviors that are not usual for him; like having accidents in the house, being aggressive, fearful, or overly reactive, you should call your vet! A trainer cannot “fix” behaviors that are a result of an underlying medical condition.
From Jan Rasmusen “Many of these and other canine “problem” behaviors can result from thyroid dysfunction, or a vaccine or drug reaction. Even food with a high sugar content can cause behavior problems, as it can with children.”