Purpose: 

Borderline personality disorder and bipolar disorder are commonly confused for each other by mental health professionals which frequently leads to inappropriate and harmful treatment. Misdiagnosis can be caused by confusion of similar symptoms found in both disorders, overall lack of education in both disorders, and gender and racial bias. This paper aims to explain the disorders in simple terms, showcase key differences between the disorders, point out potential biases, and assist mental health professionals and students in understanding the complexity of borderline personality disorder and bipolar disorder. It also includes bias checking questions as well as some examples of diagnostic questions to ask a patient to clarify any symptom similarities they are presenting.