Sorry to see so many fellow sufferers.
I've had them for 33 years, usually for a three month period as often as annually, but up to three years occasionally.
I've seen all sorts of specialists, and on a few occasions received treatments that seemed to work. As the years passed I realised what was happening. Start a period of CH. Make appointment to see (almost always different) GP. Let him have a shot. Get referred to Consultant. Appointment is now some months into the cluster, so anything suggested coincides with the end of the cluster, and seems to have worked.
The only thing that did really seem to help was Oxygen at 100% by special mask. (100% is too dangerous for patients with breathing problems so they are not normally handed out). Snags are that you might fall asleep with the mask on. two outcomes. Oxgen runs out. Oxygen is pretty dangerous - explosions wise.
The definites are:-
Having several hundred headaches, and the corresponding quantity of painkillers turned me into a Zombie. No sleep (almost too scared to go to sleep) and overdosed. Because I never really looked for sympathy it never really ocurred to me to discuss this with employers. So. Careers ruined.
There is no point in taking normal painkillers as directed. For one, they aren't really even kicking in when a shorter headache is on it's own way away.
I'm now going to make myself look like a complete idiot. But it works for me.
Given that the O2 seeemed to work, and also that I was always drawn to cool places, I wondered if cold was the answer.
So. Here goes. Tried lying on the kitchen floor with the freezer door cracked open, inhaling the cold air. It worked.
O2 isn't really the answer (imho) it's the fact that it's cold, and at 100% more cold than the normal 25% + 75% ambient air would be.
So for the last three episodes I have kept loads of ice in the freezer, and lots of water in the fridge. When I went out, I took a load in an insulated bag. Headache coming on? Water into ice, then hold water in mouth until it's warming. Repeat, and keep repeating until it's easing, cooling the brain either 'externally' with cold air, or internally with the ice/water.
So feel much better without the overdose.
Trouble is, mine get more and more frequent and more and more painful, so I've not managed to go through a whole episode without the painkillers.
One tip for taking stuff like Ergotamine, Paracetomol etc.. crunch them up and dissolve with Tonic water. (only as much as a couple of mouthfuls) again, hold in your mouth for as long as poss. Bubbles seem to help it into the bloodstream faster.
I have a theory about why the cold works, but it's too long to go into. If any of you find that it works for you, please let me know, and we could take it to some of the scientists who have researced CH.
Lastly. For various reasons I've been on Cipralex (an anti-depressant) for five years, more or less continuously. No headaches for five years - longest ever.
edit. In my case we eliminated all known triggers (thanks be) and the only stress connection that I ever noticed was that they came as stress was removed. Good examples, after finishing a yacht race, a long fast drive UK to Alps.