Hello and thanks for posting your question on JustAnswer.com. I putting together some questions that will help me learn more about what’s going on with your pet.
Boxwood is indeed toxic to reptiles though I don't know if a leaf is enough, though she is a young dragon. She has been lethargic since before or after her large meal yesterday at dinner time? Is there anything else she could have gotten into or could she have injured/fallen?
If she is lethargic from the boxwood ingestion, treatment is fluids (preferably IV but for a small dragon a veterinarian can give them under the skin or into the abdomen) and oral activated charcoal at a dosage of 2 mg/kg given four or more times per day. The injectable fluids are not something you can do at home. I would start by giving her a soak in some warm water in case she's dehydrated and would consider having her seen by a local veterinarian with experience in reptile medicine.
The soaking would be helpful in case it's indigestion and not intoxication.... Please let me know if I can be of any further assistance.
All my best to you and your dragon. Please contact me if you have any other questions and thank you for using JustAnswer.com
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