Grapefruit juice combined with Vitamin D drops caused me a lasting headache, which, in hindsight, was like a sinus infection without the sinus infection part, but including the typically incredibly stiff neck.
Lasting here means a whole month. One month of continuous headache. Not headaches. One gigantic headache. Mostly 7/10, two times 9/10, at which points we called the ambulance because I couldn't take it anymore.
Don't ever mix grapefruit juice with anything.
How much vitamin D were you taking?
How much time was there between taking vitamin D and drinking grapefruit juice?
There was no time in between taking it and drinking the juice. It was what I drank most of the day.
One can take a few of these drops (liquid, in case that's unclear) every day, but that makes my stomach gas up massively for some reason.
One can take them once a week, too, but then he had to take the whole weekly dosage at once. Apparently it doesn't matter. I don't remember how much it was, but I'm talking about one or two dozen water droplets here. I'm sorry, I don't know how to express this any better.
The headache started maybe two hours later.