Dog Health Questions? Ask a Dog Vet for Answers ASAP
There are many different things that could be causing his problem. Since he has been normal for the last several years, it sounds likely that this is a medical problem rather than a behavioral issue.
I would consider a urinary tract infection, urinary stones, Cushings disease, or diabetes on the top of the list. I recommend having him seen by your regular vet. I would start with a physical exam and a urine sample. Depending on the results, we might need to proceed with more tests including bloodwork and xrays. At that point, your vet should have a diagnosis and be able to begin a treatment plan.
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