Ouzo

I've found 200mg caffeine pills to help abort...along with an NSAID pain reliever. Just don't take on an empty stomach.

And don't ever, ever not take these headaches seriously and try to tough them out. I've been chastised by doctors and nurses who have told me cluster headaches can be a medical emergency. If they're bad enough for you to think about suicide, and treatment isn't helping, get to the ER on the double! They really are worse pain than most people can even comprehend.