Thank you for your patience. There are two key concerns here as you are probably aware for your girl. One is the chocolate content of the drink, which while it is probably low, may potentially be enough of an issue for such a small dog. The key issue here though is the alcohol she has ingested. It sounds like you are definitely seeing the effects of this ingestion now with the ataxia, vomiting and shivering. The effects of the alcohol ingestion will worsen in the next little while and because she is only 12 pounds, you may see further symptoms including anything from further vomiting, weakness, diarrhea, abdominal pain, lethargy, collapse and potentially even seizures and coma. Because your girl had potentially 3 - 4 ounces of this and she is only 12lbs, we could definitely see some severe symptoms here.
For this reason, I would definitely recommend that you get her down to your local ER vet right away. Here they can start her on intravenous fluids to keep her hydrated, give her an antiemetic to stop the vomiting, and give oral activated charcoal to help absorb any remaining alcohol in her system. Because the potential symptoms here are so serious and you are already seeing some marked ataxia within an hour, it is definitely better to play it safe and have her seen.
Head down to your local ER vet right now if you can. If you can't go straight away, you need to try and encourage her to drink plenty of water and keep her quiet and relaxed until you can get her seen. Best of luck with your girl. If you have more questions or if I can help in any other way, please do not hesitate to ask! If you would like to accept my answer, please press RATE OUR CONVERSATION (I am not compensated in any other way). Bonuses are always welcome. Thanks! I hope to work with you again soon!
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