I was treated for depression for years and years. It wasn't until I finally got in with my pdoc on a long enough basis that he could really track my symptoms over time that he reached the bipolar diagnosis. I think even he treated me well over a year, maybe two, before he decided what he was seeing was bipolar because I spend the vast majority of my time depressed. But he finally saw me go into awful suicidal mixed episodes several times and changed the diagnosis to bipolar.