I've also read that people with bipolar disorder are more likely to commit suicide as their depression lifts.

But antidepressant effects can be very complicated. I know someone who says one med made her really really want to sleep with her feet where her head normally went. I once reacted to an antidepressant by spending three days cycling through the thoughts, "I should cut off a finger" (I explained to myself why that was a bad idea) "I should cut off a toe" (ditto) "I should cut all the flesh from my ribs" (explain myself out of it again), then back to the start.

The akrasia-lifting explanation certainly seems plausible to me (although "mood" may not be the other relevant variable--it may be worldview and plans; I've never attempted suicide, but certainly when I've self-harmed or sabotaged my own life it's often been on "autopilot", carrying out something I've been thinking about a lot, not directly related to mood--mood and beliefs are related, but I've noticed a lag between one changing and the other changing to catch up to it; someone might no longer be severely depressed but still believe that killing themself is a good course of action). Still, I would also believe an explanation that certain meds cause suicidal impulses in some people, just as they can cause other weird impulses.