> that headache is caused by something

Thanks for the diagnosis, Dr. Internet Rando.

> you'll be much better taking an anti-allergic, or a sinus cleaner, or whatever else actually solves the underlying issue or make the specific symptom go away.

You can't even say what I should take. X or Y or... whatever else? That's not helpful at all.

If you don't know what causes a random headache, that's a good reason to ask a doctor.