[nowahe]

From personal experience, I feel like the crash following a multi-day binge isn't necessarily due to amphetamine withdrawls, but more so the consequences of multi-day sleep deprivation, dehydration, under-nutrition; all the while having over-exerted yourself.

On the comedown of a multi-day binge, I don't feel depressed per se. I'm constantly tired while awake, which I can only keep at bay if I'm physically active. Also, my ability to focus and get motivated dips below baseline, inversely proportional to how high over baseline I was. (And I would speculate that it is mostly due to a depletion of dopamine & its precursors rather than a withdrawl, as it can be alleviated through a decent diet).

From what I've read as well, most of the long term side effects of amphetamine abuse stem from chronic lack of sleep, food & water rather than damage from the molecule itself. Although repeated overstimulation of your reward/dopaminergic system definitely can't be good for you, be it through adaptation or damage of the dopaminergic neurons (I remember reading somewhere that long term meth users are more prone to Parkinson's).