Since 1990, interest has resurged in promoting CSP products as “essential” mineral supplements with multiple health claims (Roma Egli, FDA Nontraditional Drug Compliance Branch, written communication, February 1995). For example, advertising materials in health food stores promote CSP use in more than 650 different diseases. Colloidal silver proteins are being touted as powerful antimicrobials against viruses, bacteria, parasites, and fungi, including human immunodeficiency virus (HIV), herpes, Candida, and tuberculosis. The CSP’s also have been advertised as “an immune system stimulant and anti-inflammatory agent,” for use in conditions such as diabetes, chronic fatigue syndrome, allergies, and cancer. One manufacturer quoted a researcher in an unpublished article, “If we cannot assimilate silver for some reason or as the tissue ages, we develop a silver deficiency and an impaired immune system leading to cancer. When silver was present, the cancer cell dedifferentiated and the body was restored.”
Initially available in northwestern states, CSP’s are now widely available throughout the United States because of aggressive marketing by distributors. They are recommended for use in adults, pregnant and lactating women, and children; they are available as oral solutions, aerosols, intravaginal douches, and injectables; and they are labeled as nontoxic and void of drug interactions. Recently, combination products became available as mixed mineral supplements and as a mixed CSP – colloidal copper-menthol product for minor skin ailments.
Contrary to these promotional claims, silver is not an essential mineral supplement and has no known physiologic function. The use of silver products as germicidals has chiefly been replaced. Efficacy claims for the treatment of infectious diseases such as tuberculosis, malaria, and systemic fungal infections or for the prevention of cancer, acquired immunodeficiency syndrome (AIDS), and diabetes remain unproven. Use of such products with unsubstantiated claims can delay appropriate medical intervention, resulting in deleterious consequences.
Silver is not without toxicity. Silver accumulates in the body and may result in bluish skin discoloration (argyria). (2) While silver deposits derive from dietary (eg. mushrooms, milk, and bran), environmental, or industrial exposures, the indiscriminate use of CSP’s and other silver medicinals adds unnecessary exposure and may result in argyria. Although primarily a cosmetic concern, argyria is irreversible and has no effective treatment. In addition, neurologic deficits (3) and diffuse silver deposition in visceral organs (4) have been reported with long-term use of oral silver products. Renal damage and metal fume fever have been reported with high silver exposures. We are concerned that renewed interest in CSP’s among health food enthusiasts could lead to increased toxicity. The Food and Drug Administration’s Nontraditional Drug Compliance Branch is currently evaluating the legitimacy of marketing these products. Meanwhile, to provide proper advice to their patients, it is essential for physicians to query over-the-counter drug and food supplement use.
- Man C. Fung, MD
- Michael Weintraub, MD
- Debra L. Bowen, MD
- Food and Drug Administration
- Rockville, MD
Below are 4 of the best immune system support products available today:
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- Greene RM, Su WPD. Argyria. Am Fam Physician. 1987;36:151-154
- Westhofen M, Schafer H. Generalized argyrosis in man: neurological, ultrastructural and x-ray microanalytical findings. Arch Otorhinolaryngol. 1986;243:260-264
- Marshall JP, Schneider RP. Systemic argyria secondary to topical silver nitrate. Arch Dermatol. 1977;113:1077-1079.