A non-drug diagnosis is possible. He could have had a seizure from light/sound and then fallen and had some sort of C-Spine injury. While strokes are uncommon for his age, I just had a 20 year old in great physical shape with a CVA the other day. All sorts of possibilities. However, the vital signs, for me, would not suggest drugs, stroke or C-Spine. I would lean towards a post-ictal state. I wouldn't think it's an absence seizure as you could communicate through blinking.
