....I do believe that people with bipolar disorder have mood lability not necessarily qualifying as any episode. That's known in many circles. As for anyone having mood shifts during the day that aren't "bipolar-related", sure. Fern's point is definitely valid. Regular folks don't usually feel fatigued and suicidal in the morning and elated and ultra high energy in the afternoon for no really major reason. How do us folks with bipolar disorder really know where the limits are unless we've truly learned what stability is. I think I know what regular "non bipolar" mood shifts are. I think Fern does, too. I also know what I regard as "mood lability" that is still outside the norm. This term also apples to the major drastic shifts that people with borderline personality disorder experience, but they don't own the term exclusively. That disorder has almost mandatory dx criteria that most people with bipolar disorder never meet.