In my experience, Selenium is one of those supplements that one can have a reaction to. When I first was diagnosed with mercury poisoning my MD put me on 200 mgs of Selenium and I "suddenly" could not go out in public places, became fearful and highly anxious and suspicious of everyone. Bernie of DAMS had told me to be careful of this supplement before, when I remembered this, I stopped taking it and within 2 days I was back to normal.

I tried a few months later, same reaction. Now it's in small doses in one of my daily supplements (33 mgs) and that seems to work well.