Across 29 studies, St. John’s Wort was found to be more effective than placebo and just as effective as Prozac in treating mild to moderate depression. However, it should be noted that the researchers stated that some of the smaller German studies may have had “over-optimistic results”.

Keep in mind that in some countries, like Germany, herbals/neutraceuticals are regulated by their equivalent of the Food and Drug Administration (FDA). In the United States, herbals/neutraceuticals are not regulated by the FDA, so you need to make sure you check the quality assurance standards of herbal/neutraceutical manufacturers.

Also keep in mind that these studies examined the effects of St. John’s Wort on mild to moderate depression, not severe depression. I don’t have any information yet about how these studies were conducted, so I’m not sure of the methodology used or how the treatment effectiveness was measured.

Also let your healthcare provider know if you are taking any herbals/neutraceuticals – some can affect the central nervous system (CNS) and may cause interactions with your medications.

Information on the study can be found here:

St. John’s Wort Study