It’s possible your dog is suffering from the beginnings of vestibular disease. Symptoms include standing with legs spread out, swaying, head tilt, abnormal eye movement, walking sideways, falling over and may include vomiting. There are a few things that can cause this condition such as an ear infection, some medications and old age. Since your dog is scratching her ears often, then an ear infection on the side she is falling toward might be the issue.
Here are some great sites on this condition:
Old age is often a cause as well and if this is the case, the condition normally resolves itself over a few weeks. Your vet will most likely prescribe dramamine or bonine to help with the symptoms. You can read about dramamine and bonine usage, precautions and dosage here:
Now if she had access to antifreeze, that can cause similar symptoms of a drunk like walk. In that case you need to get her to a vet immediately. Read more on this here:
Now older dogs can experience strokes as well. A stroke can also cause similar symptoms. With a stroke you often see improvement within a week and in many cases a full recovery is possible. In others a dog might still experience some lasting changes. Read up on strokes here:
I'd recommend you have her in to see your vet since incoordination can also be due to organ failure and she is an older dog as well. Your vet should be able to determine if an ear infection is the cause fairly quickly and help resolve the issue.
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