Hello, and thanks for writing in.

Many things can cause the panting and pacing, such as restlessness, anxiety/stress, pain, internal metabolic disorders. The purple tongue is even more concerning, as this color of mucus membranes and tongue can indicate lack of oxygen getting to tissues in the body, which can also occur for various reasons (heart problems, respiratory problems, fluid in the lungs or chest, among others. I would highly recommend getting Pandy into a veterinary clinic tonight, if at all possible (ER clinic, or on-call veterinarian) so the underlying cause can be found, and she can be treated appropriately. If this is not possible for you to do, try to keep her as calm and confined as possible (no stress, excitement, etc.) If she will not calm down at all, you can try plain over the counter Benadryl (diphenhydramine) at 1mg per pound of body weight, as this can cause a relaxing effect in some dogs.

I hope this helps.

Dr. Dave