Written by: A. Lee
Amy Lee has been quoted saying the song is about losing the comfort of sorrow. Lithium is a mood stabilizer that would take away the sorrow that the writer holds inside and she is not ready to let go of it. She has lived with sorrow so long that losing it now would be like losing a part of herself. That is what the whole refrain is about: "Lithium, Don't want to lock myself up inside, Lithium, Don't want to forget what it feels without, Lithium, I want to stay in love with my sorrow." . It's about her inner feelings toward herself.
She first wrote the chorus on guitar when she was about 16, but left it there. Eventually she started playing it on the piano, and the verses came out. "I have a pile of pieces stowed away in my mind that maybe I'll use some day. In a way it's an old song, but not really; It grew up."