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Saint John’s Wort

Hypericum perforatum

Found: in fields and roadsides throughout our area. It is a common, though non-native, roadside herb.

Height: up to 1 meter (3 feet) tall

Leaves: oblong, with translucent glands visible

Flowers: yellow, with five petals surrounding a cluster of stamen. The petals have black dots visible on their margins

Uses: the plant has been used to treat mild to moderate forms of depression. It has undergone more than 20 clinical trials which have found it to be both safe and effective. Compounds found within the plant have been shown to regulate levels of compounds such as dopamine, interleukins, melatonin, monoamine-oxidases, and serotonin. Experiments have also shown it to have sedative, anti-inflammatory, and antibacterial uses. Further studies have also shown that it contains the biological compounds hypericin and pseudohypericin, which have strong anti-retroviral activity without the risk of serious side-effects. It is currently being researched for possibilities in AIDS treatment.

St John's Wort leaf