Colloidal Silver:
Risk Without Benefit

Stephen Barrett, M.D.
Colloidal silver is a suspension of submicroscopic metallic silver particles in a colloidal base. Long-term use of silver preparations can lead to argyria, a condition in which silver salts deposit in the skin, eyes, and internal organs, and the skin turns ashen-gray. Many cases of argyria occurred during the pre-antibiotic era when silver was a common ingredient in nosedrops. When the cause became apparent, doctors stopped recommending their use, and reputable manufacturers stopped producing them. The official drug guidebooks (United States Pharmacopeia and National Formulary) have not listed colloidal silver products since 1975.

Dubious Ads
In recent years, silver-containing products have been marketed with unsubstantiated claims that they are effective against AIDS, cancer, infectious diseases, parasites, chronic fatigue, acne, warts, hemorrhoids, enlarged prostate, and many other diseases and conditions. Some marketers claim that colloidal silver is effective against hundreds of diseases.

During 1997 and 1998, Changes International, a Florida-based multilevel company, stated:

Our colloidal silver contains 99.99% pure silver particles suspended indefinitely in demineralized water that kills bacteria and viruses. It can be applied topically and/or absorbed into the blood stream sub-lingually (under the tongue), thereby avoiding the negative effects of traditional antibiotics that kill good bacteria in the lower digestive tract.

An all natural antibiotic alternative in the purest form available. The presence of colloidal silver near a virus, fungi, bacterium or any other single celled pathogen disables its oxygen-metabolism enzyme, its chemical lung, so to say. The pathogens suffocates and dies, and is cleared out of the body by the immune, lymphatic and elimination systems.

Unlike pharmaceutical antibiotics which destroy beneficial enzymes, colloidal silver leaves these beneficial enzymes intact. Thus colloidal silver is absolutely safe for humans, reptiles, plants and all multi-celled living matter.

It is impossible for single-celled germs to mutate into silver-resistant forms, as happens with conventional antibiotics. Also, colloidal silver cannot interact or interfere with other medicines being taken. Colloidal silver is truly a safe, natural remedy for many of mankind's ills. Colloidal silver can be taken indefinitely because the body does not develop a tolerance to it [1]

Seasilver International, a California-based multilevel company, claims that American are suffering from "silver deficiency." Although silver is not an essential nutrient, product information posted on the company's Web site states:

The depletion of minerals in our soil has left us deficient of silver, one of our most essential trace minerals, causing a drastic increase in immune system disorders in our society in the last decade. Research has taught us that all disease is allowed to manifest itself because of a weakened immune system. In over 20 years of worldwide research on Colloidal Silver, numerous interviews with government agencies, health care practitioners and their patients, no other nutrient, herb or drug (prescription or over-the-counter) is as safe and effective against all known forms of unfriendly virus, bacteria, and fungus. Additionally, while it is generally known that most antibiotics kill only perhaps 6 or 7 different disease organisms, reports have shown that Colloidal Silver has been used successfully in the treatment of over 650 diseases! Furthermore, strains of disease organisms fail to develop in the presence of Colloidal Silver. Colloidal Silver's greatest attribute is its unique ability to function as a superior second immune system in the body! [2]

The ad below is from the July 1996 issue of Alternative Medicine Digest.


Critical Studies and Case Reports
In 1995, an herbal distributor named Leslie Taylor tested nine commonly marketed colloidal silver products available at health-food stores and concluded:

Two of the products were contaminated with microorganisms.
The amount of silver suspended in solution varied from product to product and would gradually decrease over time.
Only five products actually showed antibacterial activity in a laboratory test. To perform the test, she prepared a culture plate with Staphylococcus aureas bacteria, which can cause infections in humans. She then placed a drop from each product on the plate and used disks of two common antibiotics as controls. After eight hours of incubation, she found that bacterial growth had been inhibited around the antibiotics and four of the products.
Of course, the fact that a product inhibits bacteria in a laboratory culture doesn't mean it is effective (or safe) in the human body. In fact, products that kill bacteria in the laboratory would be more likely to cause argyria because they contain more silver ions that are free to deposit in the user's skin.

FDA laboratory studies have found that the amount of silver in some product samples has varied from 15.2% to 124% of the amount listed on the product labels. The amount of silver required to produce argyria is unknown. However, the FDA has concluded that the risk of using silver products exceeds any unsubstantiated benefit [3]. So far, nine cases of argyria related to silver products have been reported:

A 56-year-old man who had sold and used colloidal silver for three years, developed blue/gray discoloration of his fingernails accompanied by a very high blood level of silver [4].
A married couple who had three years of daily consumption of a drink prepared by administering an electrolytic charge to a bowl of water that contained a silver bar [5].
Another couple had been taking a silver-containing "dietary supplement" prescribed by a naturopath [5].
A mentally ill man who had been drinking silver-containing herbal tea for about 10 months [5].
Stan Jones, Montana's Libertarian Party candidate for the U.S. Senate, who reportedly started taking colloidal silver in 1999 for fear that Y2K disruptions might lead to a shortage of antibiotics. He made his own concoction by electrically two silver wires in a glass of water [6].
Two men, ages 63 and 76, developed argyria after a year of product use inspired by Internet claims [7].
Enforcement Actions
Between October 1993 and September 1994, the FDA issued warning letters to five colloidal silver marketers::

Higher Education Library Publications (H.E.L.P.), of Springfield, Utah, was ordered to stop claiming that its colloidal silver product was effective as a natural antibiotic and might be effective against cancer, genito-urinary diseases, tuberculosis, and AIDS.
Nutrition, Inc., of Arvada, Colorado, was ordered to stop stating or implying that its Silvicidal, when administered orally or intravenously, was nontoxic, FDA-approved, and was a broad-spectrum antibiotic that killed bacteria and all virus and fungal infections. In addition, it was falsely claimed to be effective against a long list of specific diseases.
Reseau International of Cincinnati, Ohio was ordered to stop claiming that its colloidal silver product was a "natural antibiotic and anti-inflammatory immune system stimulant" and that it was effective against cancer, staph, strep, influenza, general body infections, inflammation, impaired immune system, fungus toxicity, tonsillitis, Meniere's symptoms, whooping cough, shingles, syphilis, cholera, and malaria. The labeling also stated that colloidal silver could cause major growth stimulation of human tissues and can regenerate
Silverado Inc., of Bountiful, Utah, was warned to stop making false claims that its colloidal silver product was effective as an antibiotic, anti-inflammatory, anti-viral, and anti-fungal agent and that it could stimulate the immune system.
Unic, of Carmichael, California, was ordered to stop claiming that its colloidal silver product was effective against many diseases and could heal burn-damaged tissue without scarring.
In October 1996, the FDA proposed to ban the use of colloidal silver or silver salts in over-the-counter products [8]. A Final Rule banning such use was issued on August 17, 1999 and became effective September 16th. The rule applies to any nonprescription colloidal silver or silver salt product claimed to be effective in preventing or treating any disease [9]. Silver products can still be sold as "dietary supplements" provided that no health claims are made for them. During 2000, the FDA issued warnings to more than 20 companies whose Web sites were making illegal therapeutic claims for colloidal silver products.

In 2000, the Federal Court of Australia banned Vital Earth Company Pty Limited and its director Darryl John Jones from falsely representing that the colloidal silver produced by their "Vital Silver 3000 Zapper," "Vital Silver 2000 Automatic" and "Vital Silver 2000":

Can kill all disease-causing bacteria, fungi and virus within six minutes of contact
Has no harmful side effects; that colloidal silver could be used as an antibiotic for all the acquired diseases of active AIDS
Is effective with more than 650 different pathogenic bacteria and virus types
Has been used successfully against diseases including AIDS, cholera, diabetes, leprosy, leukemia, lupus, skin cancer, syphilis and whooping cough.
The company was also ordered to pay AUS$9000 in costs and to provide refunds [10].

In 2001, the FTC obtained consent agreements with two companies:

Robert C. Spencer and Lisa M. Spencer, doing business as Aaron Company (Palm Bay, Florida). Colloidal silver has been medically proven to kill over 650 disease-causing organisms in the body and is effective in curing diseases ranging from cancer and multiple sclerosis to HIV/AIDS [11].
ForMor, Inc., doing business as ForMor International, and its president, Stan Gross (Birmingham, Alabama) agreed not to make unsubstantiated claims that colloidal silver is effective in treating over 650 infectious diseases, has no adverse side effects, and is effective against arthritis, blood poisoning, cancer, cholera, diphtheria, diabetes, dysentery, gonorrhea, herpes, influenza, leprosy, lupus, malaria, meningitis, rheumatism, shingles, staph infections, strep infections, syphilis, tuberculosis, whooping cough, and yeast infections [11].
In 2002, the FTC obtained a consent agreement with Kris Pletschke, doing business as Raw Health, agreed to stop making unsubstantiated claims that its colloidal silver product could treat or cure 650 different diseases; eliminate all pathogens in the human body in six minutes or less; and is medically proven to kill every destructive bacterial, viral, and fungal organism in the body, including anthrax, Ebola, Hanta, and flesh-eating bacteria [12].

In 2002, the Australian Therapeutic Goods Administration amended its rules so that water-treatment products containing substances like colloidal silver for which therapeutic claims are made must meet the requirements of medicines included in the Australian Register of Therapeutic Goods. This means that such products can no longer be legally marketed without proof that they are safe and effective for their intended purpose. The amendment was based on clnclusions that:

There is little evidence to support therapeutic claims made for colloidal silver products;
The risk to consumers of silver toxicity outweighs the value of trying an unsubstantiated treatment, and bacterial resistance to silver can occur
Efforts should be made to curb the illegal availability of colloidal silver products, which is a significant public health issue [13] .
References
Product brochure. Changes International, 1997. Downloaded in 1998.
Seasilver International Product Information, accessed October 12, 1998.
Fung MC, Bowen DL. Silver products for medical indications: risk-benefit assessment. Journal of Toxicology and Clinical Toxicology 34:119-26, 1996.
Gulbranson SH and others. Argyria following the use of dietary supplements containing colloidal silver protein. Cutis 66:373-374, 2000.
Hori K and others. Believe it or not -- Silver still poisons! Veterinary and Human Toxicology 44(5):291-292, 2002.
Blue Is the color of my candidate's skin. Associated Press, Oct 2, 2002
Cohen LE and others. Effects of Internet quackery: Argyria in the silver state. Federal Practitioner 21(4):9-17, 2004.
Federal Register 61:53685-53688, 1996. (To access this document, search the 1996 volume for "colloidal silver.")
FDA. Final rule: Over-the-counter drug products containing colloidal silver ingredients or silver salts. Federal Register 64:44653-44658, 1999. Download PDF version
Refunds for buyers of alternative therapy devices. News release, Australian Competition and Consumer Commission., May 5, 20
"Operation Cure.All" wages new battle in ongoing war against Internet health fraud. FTC news release, June 14, 2001.
FTC announces first two enforcement actions against purveyors of bioterrorism defense products. FTC news release, Feb 27, 2002.
Regulation of colloidal silver and related products. Therapeutic Goods Administration Web site, Aug 19, 2003.
For Further Information
Rosemary Jacobs, an argyria victim, has made a detailed study of the colloidal silver marketplace and is willing to answer questions