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Actions and Uses:

St. John's wort has been used for hundreds of years in folk medicine, especially for healing
wounds. In 1959 and 1971 St. John's wort's antibacterial properties were scientifically reported.
An explosion in the popularity of St John’s wort related to its unregulated availability for the
treatment of mild to moderate depression. In the USA, for the first eight months of 1999, it
ranked second to ginkgo as the best-selling product of the herbal mainstream market. In
Germany, it represented 25% of all antidepressant prescriptions. It was described as ‘nature’s
Prozac’, without the disadvantageous side-effects of the latter. However, a cautionary warning
was struck by two reports (S. Piscitelli et al., Lancet, 2000, 355, 547; F. Ruschitzka et al., Lancet,
548). In the first, St John’s wort was observed to lower plasma concentrations of the protease
inhibitor indinavir. In the second report, heart transplant rejection, as a result of the lowering of
ciclosporin plasma concentrations below therapeutic levels, followed St John’s wort therapy. It
has subsequently transpired that St John’s wort will adversely affect the performance of a
number of common drugs by causing their rapid elimination from the body, either by enhanced
metabolism or as a result of increased action of the drug transporter P-glycoprotein. Among
common drugs so affected are anticoagulants such as warfarin, digoxin, tricyclic antidepressant
agents, simvastatin and others.
In the UK, there are currently (2007) no specific restrictions on the sale of St John’s wort as a
herbal preparation but it is recommended that professional advice be sought if it is to be taken
in conjunction with other medicines.
Uses Approved by Commission E:
• Anxiety.
• Depressive moods.
• Inflammation of the skin.
• Blunt injuries.
• Wounds and burns.

Warning / Pregnancy:

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