The Percocet is causing the itching. Very common with pain meds. Benadryl will help or if you are like me and you will be hung over from benadryl for 2-3 days, then see if your doctor will call in an Rx for Vistaril. It's a prescription antihistamine that is commonly taken with pain meds like percocet and not only does it relieve itching (mostly prescribed for pruritis-itching), but it also potentiates the effects of the narcotic, or makes them stronger. Since you are having more pain with the block wearing off and are needing the tramadol for breakthrough pain, this might help the pain and the itching. I take Vistaril every time I take percocet and I usually don't itch. I think Joyful and Loretta take it too! HTH!