This herb is probably one of the most familiar to people based on its name alone, but it is also one of the most misunderstood. It’s fame is due to the studies on St. John’s worts’ effects on depression, as well as its potential interactions with pharmaceutical medications.
Hypericum perforatum is the Latin name; the species name refers to tiny oil glands in the leaves that can be clearly seen as “perforations” when held up to the light. The flowers are a sunny yellow that produce a rich red resin at their base, which is extracted when infused into an oil fresh or made into a tincture. This plant grows in “waste lands” such as highway medians, abandoned city lots, and edges of parking lots, as well as in lots of other areas outside urban areas. In Washington, this herb is considered a noxious weed, but as we herbalists know, many herbs that are known as weeds are supportive medicines.
St. John’s wort is used as a nerve tonic, restoring the nervous system and helping with anxiety and depression. It can also help repair nerve and tissue damage, both internally when taken in a tea, capsule, or tincture, and externally when applied as an infused-oil or salve. Because of its effect on nerves, this herb can also help reduce pain. It also reduces inflammation and promotes tissue repair. When applied topically, compounds in St. John’s wort can make the skin more sensitive to sunlight and increase chances of getting a sunburn.
Because St. John’s wort contains compounds that are metabolized through specific enzyme pathways in the liver, it can speed up metabolism of other drugs that also are metabolized via these enzyme pathways, making them detoxify out of the body faster. Some drugs of concern are oral contraceptives, antidepressant drugs, and blood thinners. If you are concerned about an negative interaction with St. John’s wort, always consult a health professional, an herbalist, or a reputable resource for a list of herb-drug interactions.