Nutmeg?
In small amounts, makes food yummy, higher amounts can send you on a trip I have been told is most unpleasant and in even higher amounts can kill you.
In fact a number of the spices in your cabinet can do a number on you if taken in high enough doses. And I do not mean in the "Cinnamon challenge" way.
Plants are very interesting.
One of our old neighbors put too much nutmeg in her coffee or something one time, and basically had a low-grade acid trip.