Eriodictyon californicum, known by its Mexican name “Yerba Santa” or “Herba Santa” in English, is a shrub that can be 2.3 m tall belonging to the Hydrophyllaceae botanical family. Native to south-western North America, from Oregon to California, it grows on dry mountain slopes at altitudes up to 1.200 m.
Its fresh leaves are chewed for their refreshing taste and to relieve thirst, and used to make an aromatic sweet tea. Extracts are used as a flavouring in baked goods, sweets, ice cream and soft drinks.
As a folk remedy, it is used as an expectorant, against spasms and lower fevers, diseases of the chest and respiratory system including asthma and hay fever. Products made from Herba Santa have also been used as a bitter remedy in pharmaceutical applications for many years.
Research shows its bitterness-masking and sweetness-enhancing activity. Medicinally, it has antibacterial properties and could act as a potential chemopreventive agent.
Its main constituents are flavanones and flavones; sterubin, eriodictyol and homoeriodictyol.