St. John's Wort & Cataracts

The lens is a clear part of the eye that helps focus the passing light or image to the back of the retina from where the nerve signals carry the message to the brain. However, clouding of the lens may occur due to old age, diabetes, eye diseases, radiation and smoking. This is known as cataract and is characterized by fuzzy vision, inability to see in dim light, double vision, loss of color intensity and sensitivity to glare. The use of certain herbs such as St. John's wort may increase the risk of cataract.

What Is St. John's Wort?

St. John's wort, or Hypericum perforatum, is a shrubby plant with yellow flowers, native to Europe, the Western United States, and parts of Asia and Africa. The leaves and flowers of the plant contain biologically active compounds known as hypericin and pseudohypericin, which are responsible for its medicinal effects. St. John's wort products are available as tablets, capsules, tinctures, teas and skin lotions.

Uses

The National Center for Complementary and Alternative Medicine states that St. John's wort supplements have been used traditionally to treat mental disorders such as depression, anxiety and sleep disorders as well as nerve pain. It can also help heal wounds, burns and insect bites. The herb may also inhibit the growth of certain bacteria and viruses and thereby help fight infections.

St. John's Wort and Cataract Link

The use of St. John's wort supplements has been associated with several side effects, including cataract. In fact, according to a study published in the October 2009 issue of the journal "Current Eye Research," hypericin present in St. John's wort supplements can significantly increase the risk of cataracts. Another study in the November 2004 issue of "Photochemistry and Photobiology" states that the use of St. John's wort supplements can induce toxic reactions in the eye on exposure to light and may contribute to early stages of cataract.

Precautions

Protecting the eyes from sunlight may help patients taking St. John's wort for depression, according to the book "Medical Botany." It is also important to remember that St. John's wort is also associated with other side effects. Hence, it is best to talk to a doctor before using these supplements to treat any condition. Also, the production and distribution of herbal supplements is not regulated by the Food and Drug Administration.