If you call poison control, they will likely tell you what I have told you, but if the ER vet won't treat her until you do, than I would call.
There are two options available to you at this time for poison control:
As the premier animal poison control center in North America, the ASPCA is your best resource for any animal poison-related emergency, 24 hours a day, 365 days a year. They have a large number of veterinarians and toxicologists on staff and are the best source of information. They will have the most current data as far as toxic doses or dangerous combinations of drugs. The charge to call us is $60 per case and they provide a follow up # and case number ***** you or your veterinarian can call them back on, any number of times (even a year later if needed)at no additional charge. Keep in mind that some products are covered by the manufacturer so the cost of the call may be covered by them. Their number is(###) ###-####/p>
Or Pet Poison Hotline: http://www.petpoisonhelpline.com/
24/7 Animal Poison Control Center
Pet Poison Helpline is a 24-hour animal poison control service available throughout the U.S., Canada, and the Caribbean for pet owners and veterinary professionals who require assistance with treating a potentially poisoned pet. We have the ability to help every poisoned pet, with all types of poisonings, 24 hours a day. Our knowledge and expertise of pet poisons will put your mind at ease when dealing with a potential emergency.
In order to provide this critical service, please be advised that there is a $49 per incident fee, payable by credit card. This fee covers the initial consultation as well as all follow-up calls associated with the management of the case.