<prompt> During treatment for Wilson disease with trientine and penicillamine, free serum copper should be kept below which level?25 mcgdl50 mcgdl75 mcgdl100 mcgdl  <response>: The normal free copper value is 10-15 mcgdL and it is often as high as 50 mcgdL in untreated Wilsons disease. With treatment, free copper should be 25 mcgdL. Reference: Harrisons Principles of Internal Medicine, 18th Edition, Page 3190 