Hi Tony,
That can indeed be a possibility. All these different headache types react on each other and I agree it is very difficult to differentiate. I heard of women who have CH and migraine, they sometimes can not tell the difference which one is active at which moment. And that is also my problem.
Oxygen in my case works very well for migraine if I am early enough. And as a migraine attack is always a trigger for a round of PH attacks, so it also indirectly works as a preventive for PH. I can abort 80 % of my migraine attacks with oxygen. That is why my triptan usage is very low compared to the number of attacks I have per month. But once the PH started, you are right the oxygen is not working anymore. Simply because the attacks are too short. Most attacks are average 7-12 minutes. In a very rare case, it can last 20 min. That is why oxygen is more or less useless as by the time you are on the oxygen and start breathing, 10 min have already passed and the attack stops by itself. But oxygen takes the sharp edges off the attacks and bring it down from 9 to 5-6. So it is a bit useful somehow. But during the attacks I am so busy trying to stand the pain that I am not able to focus on the oxygen.
Indomethacin was not fully conclusive at 150 mg (some attacks still came through) but then they increased it to 225 mg. Then the response was absolute. There was not any symptom left of these attacks and all what was left was classic migraine that went easy away with a zomig pill.
Now, 225 mg is a too high doses to take permanently (indocin is not the kind of med to take permanently anyway) and what I do now is if I feel it coming I start with 100 mg indocin and then 50 mg every 8 hours for around 3 days. Mostly these PH rounds take around 3 days with on average 20-30 attacks per day. So what I try is to cover this with indomethacin which is working well now. Indocin starts to work already in 1-2 hours and stop the attacks completely.
I asked about CH, if I can still have it but my neurologist told me that attacks that last on average 10 min with +20 per day in the active period and fully indocin responsive can not be labeled as CH. I agree with this.
But we will try to do some administrative trick to keep the compensation for my oxygen, which is exactly what you mention. Having 3 conditions so the CH diagnoses is still valid, and thus my right for oxygen compensation. Indocin by the way is also not that cheap. I pay every time 16 € for 60 pills. That is good for around 1,5 months.
Thanks and Best Regards !
siegfried