Another excellent article over at the mind hacks blog. As it turns out, honey derived from the blossoms of Rhododendron ponticum contain the neurotoxin Grayanotoxin.
This "maddening honey" was known to the ancients. Pliny the Elder wrote of it in his Naturalis Historia, a translation of which can be found here.
It may also be the case that honey produced from the flowers of nerium oleander or the almond tree (prunus dulcis) contains neurotoxins.
