St. John's Wort: Elevating Mood

St. John's Wort, the fastest growing herbal mood-booster on shelves today, is a natural for fighting depression.

By PT Staff, published March 1, 1999 - last reviewed on June 9, 2016

Named after St. John the Baptist because its yellow flowers are said to bloom around June 24, the anniversary of his execution, this plant is the fastest growing herbal mood-booster on shelves today. In Germany, it is prescribed four times more often than Prozac, making it that nation's most popular antidepressant.

More than a score of studies have shown that the plant Hypericum perforatum is effective in treating mild to moderate depression—and with fewer of the adverse effects, such as lowered libido, that accompany standard antidepressants. That record led the National Institutes of Health to study the plant.

Researchers are investigating exactly how St. John's Wort works. One focus of interest has been hypericin, a plant compound that scientists believe may regulate brain chemicals, such as serotonin and monoamine oxidase (MAO), that are critical to mood.

How to Take It: The recommended dose is 300 mg three times daily of extract standardized to 0.3 percent hypericin.

According to Germany's Commission E, St. John's Wort does not interact with other drugs. However, the U.S. Pharmacopoeia advises anyone taking the remedy to avoid antidepressant drugs, including MAO inhibitors and serotonin reuptake inhibitors (for example, Prozac, Paxil and Zoloft).

Possible side effects include abdominal pain, bloating, constipation, dizziness, dry mouth, nausea and fatigue. Pregnant and lactating women are advised to avoid St. John's Wort.