I just started running 3iu of hgh daily and am going to switch to 2iu a day for awhile due to the lethargy. Might even go to 1 iu and work my way up. I'm having trouble focusing at work. My concentration sucks and my head feels foggy. Anyone have similar experiences? I know lethargy is common, but damn! Hopefully this gets better with time. I don't know if I can stay on if this continues.