Colloidal silver

What are colloidal silver products?

Silver is a metallic element that is mined as a precious metal. It has various industrial uses--for example, in jewelry, silverware, electronic equipment, dental fillings, photographic processing, and disinfecting water. People are commonly exposed to silver, usually in tiny amounts, through the environment (such as the air), drinking water, and food, and possibly their work or hobbies. Silver has no known biological function in living organisms.

Silver has had some medicinal uses going back for centuries. However, more modern and less toxic drugs have eliminated most of those uses. A few prescription drugs containing silver are still available. For example, silver nitrate can be used to prevent an eye condition called conjunctivitis in newborn babies and to treat certain skin conditions, such as corns and warts. Another drug, silver sulfadizine, can be used to treat burns. These drugs are applied to the body (i.e., they are not taken internally), and they can have negative side effects.

Colloidal silver products consist of tiny silver particles suspended in a liquid base. Sometimes other ingredients are added, such as proteins, coloring, etc. The products are usually taken by mouth (in which case the products are considered dietary supplements). Some other types are sprayed, applied to the skin, or injected into a vein.

Some dietary supplements contain collodial silver- but it will be noted on the label.

Purported health benefits of colloidal silver

Colloidal silver products are often marketed with various unproven health-related 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).

Do colloidal silver products work?

Reviews in the scientific literature on colloidal silver products have concluded that:

• Silver has no known function in the body.
• Silver is not an essential mineral supplement or a cure-all and should not be promoted as such.
• Claims that there can be a "deficiency" of silver in the body and that such a deficiency can lead to disease are unfounded.
• Claims made about the effectiveness of colloidal silver products for numerous diseases are unsupported scientifically.
• Colloidal silver products can have serious side effects (discussed further below).
• Laboratory analysis has shown that the amounts of silver in supplements vary greatly, which can pose risks to the consumer.

Potential risks of colloidal silver

• Animal studies have shown that silver builds up in the tissues of the body. In humans, buildup of silver from colloidal silver can lead to a side effect called argyria. It causes a bluish-gray discoloration of the skin, other organs, deep tissues, nails, and gums. Argyria cannot be treated or reversed, and it is permanent. While it is not known how argyria occurs, it is thought that silver combines with protein, forming complexes that deposit in the skin and are processed by sunlight (as in traditional photography).
• Other side effects from using colloidal silver products may include neurologic problems (such as seizures), kidney damage, stomach distress, headaches, fatigue, and skin irritation. Colloidal silver may interfere with the body's absorption of the following drugs: penacillamine, quinolones, tetracyclines, and thyroxine.

Government regulatulation of supplements containing colloidal silver

The Government does regulates them, but differently than drugs. The Dietary Supplement Health and Education Act of 1994 places dietary supplements in a special category of foods. This category is regulated differently than other foods and than drugs. For example, manufacturers of dietary supplements, unlike manufacturers of drugs, do not have to prove their product's safety and effectiveness to the FDA before it is marketed. If the product is found to be unsafe after it is marketed, the FDA can take certain actions, such as removing it from the marketplace. The FDA issued a ruling in 1999 that no products containing colloidal silver are generally recognized as safe and effective. The FDA and the Federal Trade Commission (FTC) have sent warning letters to the operators of many Web sites that market colloidal silver with drug-like claims (i.e., that their product diagnoses, treats, cures, or prevents disease).

What should you do if you are using colloidal silver?

If you are considering or using a colloidal silver product, or any type of complementary and alternative medicine (CAM), talk with all your health care providers. Discussing its use is important for your safety and helps each provider make sure that all aspects of your health care are working together. This is especially important if you are pregnant, nursing a baby, or considering treating a child. You can also learn about FDA and FTC actions on misrepresentations for colloidal silver (see "For More Information" below).

More Information

Toll-free in the U.S.: 1-888-644-6226 International: 301-519-3153 TTY (for deaf or hard-of-hearing callers): 1-866-464-3615

E-mail: info@nccam.nih.gov NCCAM Web site: nccam.nih.gov Address: NCCAM Clearinghouse, P.O. Box 7923, Gaithersburg, MD 20898-7923

Fax: 1-866-464-3616 Fax-on-Demand service: 1-888-644-6226

U.S. Food and Drug Administration (FDA) Web site: www.fda.gov Toll-free in the U.S.: 1-888-463-6332

References

Agency for Toxic Substances and Disease Registry. ToxFAQs for Silver. Agency for Toxic Substances and Disease Registry Web site. Accessed at www.atsdr.cdc.gov/tfacts146.html on March 23, 2004. Fung MC, Bowen DL. Silver products for medical indications: risk-benefit assessment. Journal of Toxicology. Clinical Toxicology. 1996;34(1):119-126. Gulbranson SH, Hud JA, Hansen RC. Argyria following the use of dietary supplements containing colloidal silver protein. Cutis. 2000;66(5):373-374. FDA bans colloidal silver products, cites lack of data. FDA Consumer. 1999;33(6). Accessed at www.fda.gov/fdac/departs/1999/699_upd.html on March 2, 2004. Natural Medicines Comprehensive Database. Colloidal silver. Natural Medicines Comprehensive Database Web site. Accessed at www.naturaldatabase.com/monograph.asp? mono_id=779&brand_id= on March 23, 2004. White JM, Powell AM, Brady K, et al. Severe generalized argyria secondary to ingestion of colloidal silver protein. Clinical and Experimental Dermatology. 2003;28(3):254-256. Hori K, Martin TG, Rainey P, et al. Believe it or not--silver still poisons! Veterinary and Human Toxicology. 2002;44(5):291-292