I have had this happen with one person I had on pramipexole for really treatment-resistant depression. We were titrating steadily up and she kept doing better with every dose increase (going from spending all staring into space and ruminating about how no one had ever really loved her, never leaving the house and hiding from neighbors v. inviting family over and starting various home improvement projects like replacing a storm door by herself). Then all of a sudden we hit 1.75 and her sleep fell off a cliff (like down to 3 hrs a night), she got extremely pressured, and would burst into tears every time she happened to see a news report or anyone mentioned the existence of the police before swinging right back into excitedly talking about how she was going to install a new sink in the span of maybe 30 seconds. Her husband told her she was talking far too much and she agreed that she never seemed to be able to ever stop while she was awake and that just maybe she had too much energy.
We cut her back down ultimately to 1.5 and this didn't go away completely (previously mild-mannered, she exploded at her PCP when he did what admittedly was a poor job explaining the implications of Stage III renal disease) but her sleep got more into the 6 hour range and she could focus on one thing at a time, so she decided some degree of instability was worth it to avoid the crushing despair of the previous twenty years. This came roaring back during a period in which she was unable to get her pramipexole filled for a couple weeks but once she was back on it she felt much better again. Her 6 hours were from 9 PM to 3 AM and she was just...very awake the rest of the day but she found this pleasant, if sometimes slightly boring.
Never really used the ER clinically, sorry.