Approx. 100 Seeds/Pkg. Depressive disorder - for the last twenty or so years St. John's wort has been extensively studied in Europe, while US studies have occurred more recently. For the treatment of mild-to-moderate major depression, studies lasting up to 12 weeks (short-term studies) indicate that the Herb is more effective than a dummy drug (placebo), as well as being as equally effective as TCAs (tricyclic antidepressants).
Although studies comparing St. John's wort against SSRIs (selective serotonin reuptake inhibitor), such as Prozac (fluoxetine) or Zoloft (sertraline) have so far been more limited, there is some evidence that the herb may possibly be just as effective, and also with fewer side effects.
The Mayo Clinic concludes that there is good scientific evidence for St. John's wort's use in the treatment of depressive disorders.