I am Dr.Lisa; welcome to JustAnswer!
At 14 yrs, your dog is considered a 'senior citizen' of the dog world, and as such, he might start to show some aging changes.
It is possible that he had a stroke, however, with a stroke, we generally see signs such as dizziness, head tilt, overall weakness, rapid eye movements, etc. The diseases below are much more likely:
- Muscle wasting, most likely caused by any of the below:
- Hip dysplasia
- Spinal disc problem
Any excess body weight will make any of those problems worse. A good place to start after an orthopedic exam would be with weight control (if overweight), and some X-Rays of his spine and hips.
The OTC product of glucosamine and chondroitin greatly help some dogs and are very safe to use. There are prescription pain medications (if he has a condition such as arthritis) such as Rimadyl and Metacam which can greatly improve his comfort and mobility.
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