Kykeon
Kykeon (Gr. κυκεών, from κυκάω, "to stir, to mix") was an Ancient Greek drink of various descriptions. Some were made mainly of water, barley and naturally occurring substances. Others were made with wine and grated cheese. It is widely believed that kykeon usually refers to a psychoactive compounded brew, as in the case of the Eleusian Mysteries. A kykeon was used at the climax of the Eleusinian Mysteries to break a sacred fast, but it is also mentioned as a favourite drink of Greek peasants.