my best friend has adult ADHD. he was diagnosed when he was 15. he is currently not on medication. His mother suffers from bipolar disorder. I believe he is also suffering from multiple personality disorder, because not only does he forget memories of events that have occurred, but he also acts differently around me sometimes, and then has no memory of those different actions. he genuinely has no memory of when he changes into this flirtatious funny outgoing playful guy. this change in personality has always occurred at night. then the next day, i ask him about his actions, and he has no idea what i am talking about. My question is: does adult ADHD have any connection to multiple personality disorder? or are these two separate conditions?