[quackscience]

I get the same, and all of these tend to be a trigger for me too -- too much caffeine, dehydration, and rapid light intensity change (like looking outside and then back to my computer screen).

In addition to chugging water and staying in the dark with a face mask, I've found that taking raw honey right as it's coming on makes it go away rapidly.

My long term prevention is taking magnesium daily and LSD once or so a year. Once I started doing that the frequency went to almost zero, and whenever I don't do that they start up again.