If you surf the web or read your local newspaper, you've probably seen something about herbal supplements and their role in treating depression. Although dozens of people swear by it, St. John's Wort is still considered to be an alternative therapy by many experts.

A wild yellow flower considered to be a weed throughout most of the U.S., St. John's Wort has been used for medical purposes in other parts of the world for thousands of years. Named for St. John the Baptist (because it blooms around the day of his feast), St. John's Wort is continually being studied to try to validate its alleged benefits.

More than 30 clinical studies have been conducted over the past 22 years to evaluate the effectiveness of St. John's Wort. The most recent scientific trials in the U.S. showed that St. John's Wort is effective for mild depression but no better than placebo treatment for moderate to severe depression.

The true benefits of St. John's Wort are still being explored. If you do choose to use it, however, here is some information you'll need to know.

How do I take St. John's Wort?

Both the leaves and the flowers of St. John's Wort are harvested, dried, and put into liquid or pill form. The dried leaves may also be used as a tea.

Typically 2 to 4 grams of powdered St. John's Wort is taken three times a day for no more than eight weeks. It also may be taken twice a day as a tea made with 1 to 2 teaspoons of the dried herb.

Preparations in the U.S. have varied amounts of active ingredient in them, so be careful to note how much you're getting in your tablets.

What are the potential benefits of using St. John's Wort?

  • Reduced depression and anxiety
  • Reduced inflammation
  • Relaxed body
  • Improved sleep
  • Promotion of wound healing
  • Reduced muscle pain
  • Relief from jaundice (a symptom of many conditions that cause yellowing of the skin and whites of the eyes)
  • Reduced or relieved symptoms of gout (a type of arthritis in which a substance called uric acid is deposited into the joints, particularly at the base of the big toe)
  • Reduced digestive problems and diarrhea

What should I watch out for if I use St. John's Wort?

  • Increased sensitivity to the sun, especially if you are fair-skinned and taking large doses
  • Increased blood pressure
  • Stomach upset
  • Allergic reactions
  • Fatigue and restlessness with long-term use

Avoid taking St. John's Wort:

Always tell your doctor if you are taking St. John's Wort or any other herbal product.

Things to think about when considering use of any herbal product

  • Discuss any drugs you use, including herbal products, with your doctor.
  • If you experience side effects such as nausea, vomiting, rapid heartbeat, anxiety, insomnia, diarrhea, or skin rashes, stop taking the herbal product and notify your doctor.
  • Avoid preparations made with more than one herb.
  • Beware of commercial claims of what herbal products can do. Look for scientific-based sources of information.
  • Select brands carefully. Only purchase brands that list the herb's common and scientific name, the name and address of the manufacturer, a batch and lot number, expiration date, dosage guidelines, and potential side effects.

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This information is provided by the Cleveland Clinic and is not intended to replace the medical advice of your doctor or health care provider. Please consult your health care provider for advice about a specific medical condition. This document was last reviewed on: 8/27/2009…#9304