The Bitter Herb of Horus

Horehound, most often the white horehound Marrubium vulgare, is a downy, bitter-tasting perennial of the mint family, an old cottage-garden and waste-ground herb of Europe and the Mediterranean. Its ancient standing was high: the Egyptians are reported to have called it the Seed of Horus or the Bull's Blood and used it among the priests, and it is often counted among the bitter herbs of the Jewish Passover, though the identification is uncertain. Its long domestic use was as a cough remedy, preserved in the horehound candies and syrups still sold, a use recorded here as folk history rather than medical claim.

Modern phytochemistry has given some real support to horehound's old reputation for the chest: the plant's characteristic bitterness comes chiefly from marrubiin, a compound that has shown expectorant and mild bronchodilator activity in laboratory and animal studies, one of the relatively few traditional cough herbs with any modern pharmacological grounding, though it remains a folk remedy and cough sweet rather than a tested clinical treatment. Horehound ale, a bitter herbal beer flavoured with the plant, was also brewed in England before hops became the standard bittering agent, a once-common drink now almost entirely forgotten.