Hello I am Dr. Joey. Thanks for trusting me to help you and your pet today. I am a licensed veterinarian with over 15 years of experience. I look forward to working with you. I apologize for the delay in an expert responding to you.
Based on what you have written I am concerned your dog may have had a seizure or a stroke type event or another significant issue that has led to the profound weakness (anemia, electrolyte problem) or even a neck/spinal issue. I do wish I could narrow down this list for you, but to do so would require a physical examination followed by some lab testing.
If he is still this affected this morning, then I must recommend you get him in to be seen on emergency today. Hopefully his regular vet is open this morning and you can get him in as a work-in. This is not something that sounds like a wait-and-see approach would be a good idea.
Let me know if he has new/more symptoms or has changed. I so wish I could provide you an easy at-home treatment but I cannot. These symptoms are such that they indicate the need for him to be seen by a veterinarian immediately.
I am at a point I need to know what questions you have. I hope that the information I provided has been helpful.
Please let me know if for any reason you need further clarification, have more questions, or were expecting a different type of answer.
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