Medical Uses of Colloidal Silver
What is colloidal silver? Colloidal silver consists of minute particles of metallic (non-ionic) silver suspended in fluid. Some preparations use larger particles of silver suspended in a protein solution. These are usually called “silver protein” or “colloidal silver protein”.
Colloidal silver is widely available as a commercial product. Methods to produce colloidal silver at home have also been published on the Internet and home "generators" are being advertised. Colloidal silver can be taken orally. It can also be applied topically to the skin or in the form of eye drops or a nasal spray.
Preparations of colloidal silver are marketed as a food supplement. No oral preparations of colloidal silver have been approved by the US Food and Drug Administration (FDA) for medical use either on prescription or as over-the-counter drugs.
What are the medical uses of silver?
The use of silver as an antibacterial and antifungal agent goes back to ancient times. For example, people noticed that water stayed sweet for longer if kept in silver containers. The Pioneers of the American West used the same trick when they put silver dollars inside wooden barrels used for storing water. Metallic silver was also used in ancient civilizations for splints and surgical prostheses.
Internal use historically required silver salts, most commonly silver nitrate, in order to have silver available in soluble form. The conditions treated with orally administered silver included epilepsy, psychiatric illnesses and infectious diseases such as gonorrhea, syphilis and gastroenteritis as well as colds and flu. Silver was also used as a remedy to help people stop smoking.
Silver salts were, and continue to be used topically in the treatment of wounds, burns, skin ulcers, verrucas and conjunctivitis. Colloidal silver was approved by the FDA in the 1920s as a wound treatment.
Recently, there has been an upsurge of interest in the use of colloidal silver preparations as an alternative therapy for numerous conditions.
Phyllis and James Balch are leading proponents of this use. In their Prescription for Nutritional Healing (available through Amazon), they praise colloidal silver for providing safe and cheap protection against infections. Thus, they recommend its topical use to promote healing of rashes, sunburn, other burns, wounds and cuts and fungal infections of the nails or skin. Gargling with colloidal silver is recommended for the prevention of bad breath and tooth decay and as a treatment for mouth ulcers and toothache. They suggest colloidal silver should be used internally as a treatment for infectious disease included candidiasis (thrush) and bacterial gastroenteritis .
Extensive claims for the benefits of colloidal silver can be found on the Internet. It is said to improve the function of the immune system and to be an effective alternative to prescription antibiotics. Diseases in which colloidal silver is claimed to have a beneficial effect include: shingles and other conditions due to herpesvirus, prostatitis (inflamed prostate), cancer, diabetes, HIV infection and AIDS, lupus, pneumonia and tuberculosis.
Most recently, colloidal silver has been promoted for the prevention and treatment of swine flu.
Does colloidal silver work?
The antibacterial effects of silver are not in dispute. A number of commercial burn and wound dressings incorporate silver salts. However, no evidence-based studies have so far been published in the medical literature to support any of the claims being made for the efficacy of colloidal silver taken internally.
Following a review of the scientific literature, NCCAM (US National Center for Complementary and Alternative Medicine) came to the following conclusions regarding colloidal silver:
• Silver does not have any physiological function in the body
• Silver cannot be regarded as an essential mineral
• Silver deficiency is not a recognized condition and there is no basis for claims that some diseases could be due to silver deficiency
• There is no scientific support for colloidal silver being an effective treatment for any disease
• Colloidal silver can cause serious side effects
• There is a large variation in the silver content of different brands of colloidal silver. This is a potential risk to consumers.
The FDA also maintains that there is no scientific basis for the use of colloidal silver to treat diseases. It disputes the claim that such preparations are generally recognised as being effective and safe.
What are the side effects of colloidal silver?
Toxicology studies have not shown any form of silver to be toxic to the reproductive system, immune system or cardiovascular system. It has also not shown any carcinogenic activity.
The following side effects have been reported with colloidal silver: eye and skin irritation, gastric irritation, damage to the kidneys and liver, headache, fatigue, changes in blood cells, seizures. Colloidal silver is also thought to interfere with the absorption of some antibiotics (tetracyclines, penacillamine, ciprofloxacin and related compounds) and thyroxine.
Long-term use of colloidal silver, or the use of high doses, can result in argyria and argyrosis. Argyria is a permanent and irreversible change resulting in the skin becoming bluish-gray in color. It is most apparent in regions of the body that are exposed to sunlight. It is caused by silver forming complexes with proteins. These complexes accumulate in the skin. There they are transformed by the action of sunlight into inert silver salts, which are responsible for the discoloration. Argyrosis is the corresponding process occurring in the eyes.
Argyria and argyrosis can occur following inhalation of a nasal spray, oral use or injection of colloidal silver, or following its application to mucous membranes.
Can colloidal silver be used safely?
After reviewing reports of 70 cases of argyria caused by silver compounds, the US Environmental Protection Agency (EPA) established a chronic oral Reference Dose (RfD) of 5 micrograms of silver per kilogram body weight per day (5 µg/kg/day). This is the dose at which the risk of developing argyria reaches a significant level. For an adult of average weight (70 kg, approx. 154 pounds) this corresponds to a daily dose of approximately 350 µg silver.
FDA (US Food and Drug Administration)
http://www.fda.gov/Food/DietarySupplements/Alerts/ucm184087.htm">Consumer Advisory: Dietary Supplements Containing Silver May Cause Permanent Discoloration of Skin and Mucous Membranes (Argyria) October 6, 2009
NCCAM (US National Center for Complementary and Alternative Medicine)
http://nccam.nih.gov/health/silver/">Backgrounder: Colloidal Silver Products