Hello I am Dr. Joey. Thanks for trusting me to help you and your pet today. I am a licensed veterinarian with over 16 years of experience. I look forward to working with you. I apologize no expert has jumped in yet to answer your question.
Juniper berries are not known to be a toxin that causes fever in dogs. It is a problem in herbivores (horses/cows, etc), though. It might cause transient liver value elevation, which was not seen upon screening lab work (I would expect at least that to make us suspect the berry ingestion as the culprit). It might cause vomit/diarrhea. So, I think these may be incidental and not the primary culprit.
It is terribly frustrating that she is not improving, but it means that with this fever in combination with the vomit/diarhrea she needs at a minimum to be hospitalized with intravenous fluid therapy for rehydration (and electrolytes) and to help lower the fever. If you are not interested in hospitalization then she probably needs more than a one-time injection and needs to continue on oral Cerenia and be started on something for diarrhea. It probably would also be a good idea to recheck her chemistry profile to see if there is a delayed elevation of her liver enzymes which would then suggest toxicity exposure. This would be helpful because it may mean we continue to be patient and support her this will pass.
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