Ptisan was a barley soup, consumed as the staple food of the Greeks. Hippocrates chose to feed it to his feverish patients, because its use was very widespread in his time. Soon after Hippocrates, wheat superseded barley as the main consumed cereal in antiquity. But owing to numerous medical polemics, this barley soup survived as food for the sick up until the seventeenth century, even though barley had become an animal feed since the Hellenistic period. Polemics by Hippocrates, Galen, Ibn Zuhr or Giovanni Manardi generated authoritative and controversial texts that insured the longevity of ptisan.
