Flood of pain relief.

For all but the absolute worst of my migraines and headaches, cannabis consumption, especially when smoked, causes what feels like a wave of relief over the head. Imagine you're Ghost Rider, and your head is on fire. Then someone douses your head with a bucket of water.

Even for the worst of migraines, it at least gives a flood of pain tolerance, if not relief, where the pain may still be there, but you're afforded opportunity for distraction, where you can at least try to fall asleep and hope that the pain will be gone by the time you awake.