When you get high, you drink more water. Dehydration can cause headaches. Low blood sugar can cause headaches, have you eaten (besides candy and similar munchies)? Are you under stress? For me, not toking can cause head aches- but I'm a special case. I was almost murdered as a 3 year old- kid came after me with a hammer. I got scars on my scalp and dents in my skull and it gave me migraines. Thank goodness for cannabis! I found it at 19 and I've been toking it for 40 years. As long as I get some pot every day, no migraines! :thumbsup: :dance: Granny Storm Crow :stoned: