St. John's wort is the most commonly used and most thoroughly researched natural product for the treatment of depression. St. John's wort is a bushy shrub native to Europe but now found throughout the world. The flowering tops are used for medicinal purposes, and use has been documented for thousands of years (Kuhn 1999). The active ingredients in St. John's wort include 10 or more chemical compounds. The most likely active ingredient in affecting depression is Hypericum perforatum.
A total of 1,592 patients have been studied in 25 double-blind controlled studies (Murray and Pizzomo 1998). In the studies, St. John's wort extract produced improvements in many symptoms of depression and has been found to be as effective in the treatment of depression as antidepressants (Philipp, Kohnen, and Hiller 1999).
The main advantage of St. John's wort was found to be not a difference in treatment outcome but rather an advantage in terms of reduced incidence and severity of side effects, costs, and increased patient satisfaction.
It is not clear how Hypericum perforatum works in its ability to treat some kinds of depression but there are several theories being investigated. Evidence indicates that the inhibition of norepinephrine and serotonin reuptake may underlie the antidepressant activity.
Dosage
St. John's wort is available as a tea, powder, oil, liquid, capsule, and tablet. Dosage: 300 mg of St. John's Wort (9.3% hypercium) three times a day. It should be taken with food to prevent stomach upset.
It takes four to six weeks to be effective.
Side Effects
The major side effect with St. John's wort is mild stomach irritation. It is considered a safe herb and incidents of adverse reactions are rare; however, it is not recommended for allergic or photosensitive individuals. Safety for use in pregnancy has not been established, therefore do not use if pregnant. Drug interactions include: intensifies action of caffeine and cough and cold remedies; should not be used with other antidepressants; decreases effectiveness of birth control pills; does NOT increase alcohol effects; and does NOT combine well with other sleep aids.
Regulation:
The Food and Drug Administration does not classify herbal medications as drugs. St. John's wort is considered a "nutritional supplement," and as such is not subject to quality control regulations as are standard pharmaceuticals. Products are therefore largely unregulated, and therefore label claims of hypericum content may or may not be reliable (Gaster and Holroyd 2000).
Cost
The retail cost of St. John's wort varies depending upon the vendor. It is readily available in drug stores, groceries, and health food stores. The prices are generally lower than the cost of standard antidepressant therapy. A typical cost for 90 300-mg tablets is $8.10. This is approximately a one-month's supply. No medical appointment is needed, so careful diagnosis by a professional is not required—this can result in taking a substance that may be inappropriate for the problems the person is experiencing.
Resources: Much of the material on this sheet is quoted directly from http://www.rxlist.com/cgi/alt/stjohn.htm and is used with permission. A good second source is http://www.hypericum.com.