I have had the itching in middle of back for several years. Was diagnosed with MAC Sept of '23. Not on Meds yet, but have been dealing with excruciating pain in the upper right side of back ( shoulder blade area) for 4 months. ID and Pulmo Dr's said it's not coming from MAC. No one can get to the bottom of it. I think it may be gastro related but don't see her until May. The MAC is in my right lung. That area also itches sometimes as well as the pain. I may resort to taking the Big 3 just to see if it helps with the pain. Thank you everyone for all the information you share. I don't feel alone.