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Sept. 5, 2008 -- Media reports are abuzz today with the story of Rosemary Jacobs, a 66-year-old Vermont woman who says her skin is permanently gray because of colloidal silver.
Jacobs blames her gray skin, a condition called argyria, on colloidal silver in nasal drops that she took as needed for four years starting as an 11-year-old. She says her skin slowly turned gray. Jacobs' case was noted in May 1999 in The New England Journal of Medicine.
You wouldn't get colloidal silver exactly the way Jacobs did today. The FDA has cracked down on colloidal silver, but that doesn't mean those products are totally gone. Paul Karason, the so-called "Blue Man" in California who says he drank colloidal silver and applied it to his skin, has also attracted media attention for his argyria.
Jacobs says she wants colloidal silver supplements to carry warning labels about argyria. She also wants anyone who makes unsubstantiated claims about their safety and efficacy to be prosecuted.
What is colloidal silver, why do people take it, and what other health risks does it pose? For answers, WebMD spoke with Andrew Shao, PhD, vice president of scientific and regulatory affairs at the Council for Responsible Nutrition, a trade group for the dietary supplements industry. Other background information comes from the web sites of the FDA and the National Center for Complementary and Alternative Medicine (NCCAM).
Colloidal silver is composed of tiny silver particles suspended in liquid.
Argyria is a permanent blue-gray discoloration of the skin and deep tissues. It can result from using colloidal silver products.
Apart from argyria, the NCCAM says colloidal silver products may cause side effects including "neurologic problems (such as seizures), kidney damage, stomach distress, headaches, fatigue, and skin irritation," and that colloidal silver may hamper the body's absorption of certain drugs (penacillamine, quinolones, tetracyclines, and thyroxine).
"The products are purported to alleviate all sorts of medical conditions and diseases but there's no substantiation for that," says Shao.
Colloidal silver products are often marketed with unproven health claims. "Examples include that they benefit the immune system; kill disease-causing agents such as bacteria, viruses, and fungi; are an alternative to prescription antibiotics; or treat diseases such as cancer, HIV/AIDS, tuberculosis, syphilis, scarlet fever, shingles, herpes, pneumonia, and prostatitis (inflammation of the prostate)," states the NCCAM's web site.
No. The FDA banned colloidal silver from all over-the-counter drugs in 1999.
The FDA's 1999 ban on colloidal silver is specifically about over-the-counter drugs, not dietary supplements. But the FDA has cracked down on companies selling colloidal silver supplements that claim that the supplements cure conditions or do other things that drugs do.
Shao says that colloidal silver -- and colloidal gold and colloidal titanium -- "are not legitimate dietary ingredients. They play no role in the diet; they're not essential in the diet." But that doesn't mean colloidal silver hasn't been hawked online.
"The fact that it's on the Internet -- there's lots of stuff on the Internet that maybe shouldn't be," says Shao. "That's not an indication of FDA's blessing or lack thereof; it's more of an indication of insufficient enforcement."