Welcome to justanswer! I am Dr. Altman and happy to assist you both today!
I am so sorry to hear your dog is showing these changes. My suspicions since it is only at night is canine cognitive disorder.
I would advise a veterinary exam to rule out any metabolic or liver related changes causing his night time behavioral change. Once this is ruled out there are supplements that can be tried and if necessary medications as well to treat this new development.
Below is more information on this condition:
There are treatments for this that can help in supplement form but also in some situations medications as well.
1.) Melatonin can help with barking or increased movement at night
2.) Proneurozone which is a supplement for brain function that can help with mental clarify in senior pets. It is available through your veterinarian but also on-line at stores like amazon.com
3.) Fish oil is essential for brain function and used at higher doses to help cognitive function. For example, for his size 1000 mg EPA & DHA daily. This can be a human formula
4.) Anipryl which is a medication used for cognitive function if the above options are not helping
5.) Alprazolam (xanax) which is not intended for daily use but is effective as needed (in the diazepam or valium family)
These are all methods that your veterinarian would have available to you to assist with some of the cognitive issues and some that you should be able to purchase at a local vitamin store or on-line
I hope the above options are helpful to you but if I can assist with clarifying anything or guiding any further questions you might have please don't hesitate to ask.
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