A person who appears to have been particularly ravaged by drug use; specifically, methamphetamine (crank) or crack. Specific traits may include missing teeth, open facial sores, disheveled hair, pale complexion, dramatic weight loss, unpredictable behavior, or serious lack of personal hygiene.
Derived from the deterioration of meth addicts documented through their police mugshots ("before and after shots").
Have you seen Dave recently? He's a wreck. I don't know what he's been doing, but he's become an after-shot.