Will she eat anything soft you leave or toss her? If so, you may be able to help her yet. Ivermectin is a very safe medication we use in dogs and horses for parasites, both internal and external. In dogs, we use the injectible medication and give it ORALLY. Let me do some research. You may be able to do the same in deer. In most animals, it has a VERY wide safety margin, so you can give literally 2-4 TIMES as much with no bad outcome. It may be tonight before I can get you an answer. I have to dig out my Plumb's Veterinary Drug Handbook. I may have to call a local wildlife rescue to get the answer.