Hi dihahey,

As what was stated above, it's the truth that diagnoses are often used as more of a guideline for symptoms and billing (not to undermine the importance of an accurate diagnosis though). Also, a provisional diagnosis is sometimes made until a doctor digs deeper and rules out different possibilities before coming up with the best fit. That process can take some time, but the doc will want time to observe how your medication is targeting your symptoms. Bipolar can be difficult to diagnose since the symptoms sometimes overlap with other conditions. One that comes to mind is Borderline Personality, where most people engage in risky behaviors to escape, experience significant shifts in mood, impulsivity, etc. Past trauma can also bring out these types of patterns. Health issues (like Thyroid problems) also need to be ruled out. It's not uncommon for different diagnoses to co-occur either.

Although lamotrigine is most commonly used in Bipolar Disorder since it is approved for that (and epilepsy), I hear of it being prescribed off-label for treatment-resistent depression, Borderline Personality, OCD, Schizoaffective BP Type.... I'm sure many other things.

Racing thoughts are terrible, and I'm sorry you are experiencing them. (((Hugs))). The cause varies. For me, I get them during manic, hypomanic, and mixed episodes. However, I have read people experience them as a result of many different mental health conditions. For instance, some people with anxiety disorders and ADHD struggle with racing thoughts.

I know it's hard, but it will take time before learning more about whether the meds are working and for the pdoc to explore what would help best. Did you ever consider doing a mood chart (at least during the process) so that you can keep track of your symptoms daily? There's moodtracker.com, for instance, which has helped me. It can also serve as a guideline for your pdoc to assist you better.