I think an Elf could have drunk him under the table any night of the week personally, but all joking aside there are two sides to that coin Ezaraudin.
Anyone with common sense would check all medical reasons for symptoms such as those, and I am assuming that it was only because your friend was at such a low ebb and drained of energy through lack of food that they didn't think sensibly about it themselves.
But we should not wait until all avenues of physical explanation have been ruled out before we look for another explanation.
I too have been having the symptoms you described above.
My first thought was to renew my sheilds and then that I should visit the doctor. (Which even though I hate them was exactly what I did.)
It turns out that the dizziness and feeling faint was due in part to the fact that I am anaemic, and the dizziness and headaches were due in part to an eye problem which I am now in the middle of having diagnosed to my satisfaction.
If the doctor hadn't found anything I would have been convinced that psychic attack was more than just a possiblility.
The point I am making is just this. Before I went to the doctor and ruled out a physical cause I renewed my shields and re-enforced my protective barriers, just in case. Which I think is a sensible precaution.
The first thing to do in any situation like this is
the thing you can do first. Often a visit to the doctor must wait a day or two, if it is a psychic attack you are being subjected to and you wait to see a doctor before taking precautions then you are not helping yourself in the best way possible.
Yes look for a physical cause, but help yourself in every way you can as soon as you can and never rule out any possibility.
That's my advice anyway.

Lady C.