Herbs Can Cause Vision Problems.

• Position: Brief Article

Consumers using "botanicals" to alleviate various conditions should be aware that certain herbs have the potential to cause health or eye problems, cautions Leland Carr, III, dean of the College of Optometry, Pacific University, Forest Grove, Ore. While there are an emerging number of studies on the benefits of certain herbs, he advises that some of them can be as powerful as prescription drugs and may be harmful if taken in excess.

"The public seems to have endorsed the notion that herbal equals natural. However, there are ocular considerations for many of these products. For example, there have been reported cases of black co-hosh causing clotting in the blood vessels in the back of the eye, an intolerance to contact lenses, and changes in the curvature of the cornea." Other herbs which have been reported, documented, or suspected of causing eye problems are St. John's Wort (appears to enhance ultraviolet damage to the crystalline lens), ginseng, bilberry extract, kava kava, as well as a...