I believe the diagnosis of any mental health condition is a puzzle. Bipolar disorder is defined by certain criteria but it is still along the lines of normal human experience. What I mean is, I don't have bipolar for eixample but I do get elated at times. (I know bipolar moods last for weeks not hours as in my case.) It is a puzzle to figure out what is going on with someone in terms of symptoms and signs, and what will solve that puzzle. In the case of bipolar, mood stabilizers are the most useful treatment at this moment. This may change as science evolves.