@mjb24 @legacygsh1 I am just about to finish treatment for my cavitary MAC infection - 13 months on Big 3 with Arikayce (though had to stop Arikayce in July due to ototoxicity concerns). About a month ago my shoulder started bothering me. A lot of pain, especially with internal and external rotation. I raised with my ID doctor and she thought unrelated to treatment, something mechanical. I am scheduled to see a PT soon. But these recent posts are interesting to me as I too have been exercising less robustly due to significant fatigue from the drugs. Maybe it is the de-conditioning that can come with treatment that plays a part. My ID doctor commented that the joint and muscle pain that is associated with the antibiotics in her experience is more generalized. But certainly, what you both are describing seems more "generalized" then my shoulder pain so I think it is worth checking in with your care team and seeing what they think about a possible connection. I finish treatment in 9 days so I will certainly respond further if I notice a sharp improvement with my shoulder pain after drug cessation.