In my opinion, the first thing to do would be to get a diagnosis by a veterinarian. I would do this before trying home remedies.
It is best not to give over the counter medications and supplements (especially if they are intended for humans) unless recommended by a veterinarian that has examined your dog.
These products are not always benign and may make the situation worse.
If your current vet has not been helpful, find another one.
How can you treat a condition if you don’t even know what it is?
