What is St. John’s Wort?

St. John’s wort (Hypericum perforatum), the popular herbal remedy used to lift symptoms of depression, is taken by more than 20 million Germans on a daily basis and has become quite popular in the United States. This herbal supplement is taken internally to relieve depression without the side effects of prescription antidepressants. In a study published in the British Journal of Obstetrics and Gynaecology, researchers report that St. John’s wort may help women with PMS (premenstrual syndrome) by easing nervous tension, anxiety, and insomnia.

In a four-month study, 19 women with PMS kept track of their daily symptoms and took psychological tests to rate their emotions and physical state. During months three and four, women were given 300 milligrams of hypericin, the active ingredient in St. John’s wort, and continued to chart their symptoms. Treatment with St. John's wort for two menstrual cycles resulted in significant improvements in PMS symptoms, with greatly reduced symptoms, such as nervous tension, insomnia, crying and depression.

St. John’s Wort is available as capsules, tincture, extract, oil, and dried leaves and flowers.  St. John’s Wort can cause sensitive skin in sunlight. Moreover, because this herb can interact with prescription medications, talk to your doctor before self-medicating. (Caution: Since the mechanism of action of St John wort is uncertain, using it with antidepressants such as monoamine oxidase inhibitors and selective serotonin reuptake inhibitors is not advised. Pregnant women are advised not to take St. Johns wort.)
Hypericum, which is the term used for herbal preparations and extracts of St. John's wort, contains a variety of substances that individually or in concert may be responsible for the actions of the herb. Hypericin, one of the compounds found both in the plant and in hypericum, is often used as a marker substance to describe the strength of extracts. Some other substances in hypericum include hyperforin, hyperforin-related compounds and many other classes of plant chemicals.

Continue Learning about St. John's Wort

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.