St. John's wort has recently become enormously popular and is being used successfully to treat a variety of illnesses and health conditions. It is primarily used to treat mood disorders, such as mild to moderate depression, seasonal affective disorder, anxiety, and insomnia. St. John's wort is also being used for treating wounds, burns, and hemorrhoids. The herb is readily available over-the-counter in a variety of forms, including capsules, liquids, lotions, teas, and powders. Although St. John's wort is widely used, easily accessible, and a natural medicine, a word of caution is in order, because like any medicine, St. John's wort may be harmful too.

As St. John's wort is studied more, experts are concerned about its potential for undesirable effects. One preliminary finding shows that high concentrations of the herb may damage male fertility. Other research indicates that St. John's wort may have a role in the development of cataracts. The herb appears to damage proteins in the eyes when combined with bright sunlight. If you take St. John's wort you should wear a hat and wrap-around sunglasses when you're outside in bright sunlight.

While St. John's wort has been shown to relieve symptoms of depression, you should not take it if you are already taking an antidepressant. Talk with your doctor if you think you suffer from depression and feel you need medical help or if you are interested in replacing your antidepressant with St. John's wort. Do not attempt to treat your depression with St. John's wort if it is severe or if you feel suicidal.

St. John's wort should not be taken if you are pregnant, breast-feeding, or if you take L-dopa or 5-hydroxytryptophan (5-HTP). You should also know that the side effects of this herb may include:

• Abdominal pain, bloating, or constipation
• Nausea or vomiting
• Dizziness
• Dry mouth
• Hives, skin rashes or irritation
• Sleeping problems
• Elevated blood pressure
• Fatigue
• Restlessness

The bottom line: keep in mind that although St. John's wort is a natural substance that is available over-the-counter, you should always treat it like a medicine and consult your doctor if you are planning to use it.

L-dopa: Levodopa, a drug used in for treating the shaking and muscular rigidity associated with Parkinson's disease

5-hydroxytryptophan (5-HTP): a natural compound produced by the body from an amino acid (tryptophan). It is used to aid sleep, and in the treatment of fibromyalgia and depression.

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