Colloidal silver is a liquid suspension of microscopic particles of silver. The technical definition of a colloid is a chemical mixture where one substance is dispersed evenly throughout the other and the particles remain suspended without dissolving in the solution. Colloidal silver is an alternative medicine product that contains a variety of concentrations of silver compounds bound to proteins in the water.
Historically, silver has had medicinal properties going back for centuries. In the early 1900 it was used as an anti-microbial to kill bacteria. A few prescription drugs that contain silver are still available today. Prior to the introduction of antibiotics colloidal silver was used as a disinfectant. It was also used on the surface of burns to control infection.
Today, colloidal silver is marketed for both internal and external uses. Unfortunately there have been unsubstantiated claims that colloidal silver is effective against AIDS, cancer, chronic fatigue, acne, hemorrhoids, prostate problems, parasites, infectious diseases and warts. Others claim that colloidal silver is effective against hundreds of others diseases without substantiation from the medical literature.
In some smaller studies researchers have found that silver continues to have some antibacterial properties in the laboratory but have not found this to be the case in clinical trials. FDA laboratory studies have found that these silver and product samples will vary between 15% and 124% of the amount listed on the product label. This means that the actual product had significantly less or significantly more silver than the products was labeled. (1)
At the current time there is no evidence-based medical use for anyone to ingest colloidal silver and there have been a few reports of toxicity. (2) Colloidal silver is available at health food stores and marketed over the Internet as a dietary supplement. However, marketers are not allowed to make claims of any medical effectiveness of the products. At this time researchers are not aware of silver as an essential mineral in humans and there is no dietary requirement for it as well. (3)
Researchers do know that chronic intake of any product which contains silver can lead to a condition known as argyria. In this condition the individual will turn blue or gray on the skin and it can lead to silver deposits in the eyes and other organs. The discoloration occurs when silver is deposited in the skin and then darkened by the sunlight. This is similar to the use of photographic film that is darkened when exposed to sunlight.
Argyria can occur locally as a result of topical use but can also be generalized to the entire body when someone has ingested, or eaten, colloidal silver. Unfortunately, the condition is permanent and there is no known effective treatment at this time. It is usually benign and limited to the skin but there have been some reports of more serious neurological and renal complications. (4,5)
At this time, colloidal silver has the status of a dietary supplement in the United States and it can be promoted with a general claim but cannot be marketed as preventing or treating any illness. In 2002 the Australian government found that there were no legitimate medical uses and no evidence to support marketing claims and concluded that it was a significant public health issue. (6)
Between 1993 and 1994 the food and drug administration issued different warning letters to five different marketers who were selling colloidal silver in an effort to stop the unlawful marketing practices. For instance, in 2009 the FDA issued a warning letter to EFT Biotech Holdings stating \”The therapeutic claims on your website establish that these products are drugs because they are intended for use in the cure, mitigation, treatment, or prevention of disease. The marketing of these products with these claims violate the Act.\”(7)
Much of the legal ramifications have occurred between Australia and the United States as these seem to be the two countries where colloidal silver has apparently been marketed most successfully and aggressively.
While there has been some significant use of colloidal silver for topical anti-microbial prior to the discovery and manufacture of antibiotics, the use of colloidal silver at this time presents more of a risk to the individual than it has any benefit.
(1) Department of Health and Human Resources Food and Drug Administration: Over-the-Counter Drug Products Containing Colloidal Silver Ingredients or Silver Salts
http://www.fda.gov/ohrms/dockets/98fr/081799a.txt
(2) Dermatology Online Journal: Systemic Argyria Associated with Ingestion of Colloidal Silver
http://dermatology.cdlib.org/111/case_reports/argyria/wadhera.html
(3) National Center for Complementary and Alternative Medicine: Colloidal Silver
http://nccam.nih.gov/health/silver
(4) New England Journal of Medicine: Argyria
http://www.nejm.org/doi/full/10.1056/NEJM199905203402006
(5) International Journal of Dermatology: Successful Treatment of Argyria using a low-fluence Q-Switched 1064-nm ND:YAG laser
http://www.ncbi.nlm.nih.gov/pubmed/21595676
(6) Australian Government Department of Health and Ageing: Colloidal Silver and Related Products
http://www.tga.gov.au/industry/cm-colloidal-silver.htm
(7) CaseWatch: FDA Warning Letter
http://www.casewatch.org/fdawarning/prod/2009/eft.shtml