Same here, I'll be fine, then bang I start getting like shiney sharp lines in my vision that spread from the outside to the center. When this happens I absolutely can't work, I can barely see anything (last time my vision was so messed up I couldn't read the pamthlet on my new migraine pills to know if I was to take 1 or 2).

SOmetimes it can knock me out for a day, but sometimes after half an hour or so I'm good to go (especially if there is no pain accompanying it).

I've never had to give more explanation than "Sorry, migraine, I need to take rest of day off, see you tomorrow".

I have always had a hard time convincing people that I don’t have a headache, I have a migraine. The pain is not guaranteed, but I am still useless.

One of my worst examples was that I made it to work on the bus, and immediately had to take off. I was pretty nauseous by the time I made it home, and should I have been found throwing up in a bush, nobody would have believed “I have a migraine”. To the drunk tank with me, at 930am.

> and I don’t always give more explanation than “taking a sick day”.

And that's entirely justified; your health is a private matter. If your employer is suspicious, there's ways and means that don't involve sharing your medical history with either your colleagues or employer.