How It Works
Bottom Line: Colloidal silver cannot cure cancer, AIDS, or diabetes. Taking too much colloidal silver by mouth can cause skin discoloration, seizures, and kidney damage.
Colloidal silver is a suspension of tiny silver particles in a liquid. Silver compounds are used externally to stop or prevent infections but recently, many people have started taking colloidal silver as an alternative medicine. It is being promoted as a cure for cancer, diabetes, and AIDS although there is no proof it works in humans. Our body does not need silver to function normally. Silver actually denatures proteins and can make many enzymes lose their effects. Long-term oral use of silver can make the skin turn bluish-gray or gray-black in color. It can also cause seizures and kidney damage. Pregnant women should not consume colloidal silver as it has harmful effects on the fetus.
Purported Uses
Immune system stimulant
No scientific studies support this use
Diabetes
There is no data to support this use
AIDS
There is no scientific evidence to support this use
Cancer
This use is not supported by scientific studies
Infections
Silver compounds have been used as topical antiseptics but there are no scientific studies to support the oral use of colloidal silver for infection
Research Evidence
No human studies have been conducted to test the medicinal effects of oral colloidal silver. There are a few case reports on its toxic effects.
A 71-year old man developed seizures and coma following ingestion of one ounce of colloidal silver and various herbal remedies for prostate cancer for 4 months. He remained in a vegetative state and died five and a half months later despite extensive treatment. Researchers concluded that the neurotoxicity and the resulting death was due to ingestion of colloidal silver.
According to another case study, a 65-year old male developed skin discoloration but had no other symptoms. He had consumed colloidal silver supplements for two years for treatment of diabetes. The discoloration was limited to fingernails but could not be treated. The patient was advised to use sunscreens to prevent further pigmentary changes.
A recent case study reported that a 56-year old man developed bluish discoloration of fingernails (argyria) following consumption of colloidal silver for cold and allergy for 3 years. There was no improvement in the appearance of fingernails 3 months after the patient stopped consuming colloidal silver. He was advised to avoid sun exposure to prevent further discoloration.
Warnings
The Food and Drug Administration (FDA) issued a consumer advisory about the risk of argyria, permanent skin and mucous membrane discoloration, associated with use of dietary supplements containing colloidal silver.
Do Not Take If
You are taking antibiotics (colloidal silver can reduce the effectiveness of antibiotics such as tetracycline and quinolone).
You are taking penicillamine (colloidal silver can reduce the effectiveness of penicillamine)
You are pregnant (colloidal silver can cause developmental abnormalities in the fetus).
Side Effects
Argyria (skin discoloration)
Kidney damage
Seizures
Common Name
Silver Proteins, Colloidal Silver Proteins, Colloidal Silver Water
Clinical Summary
Colloidal silver consists of silver particles suspended in a liquid. It is often produced by home-made generators. The use of silver medicinals to treat disorders such as epilepsy, gonorrhea, and colds was not uncommon until the mid-20th century. However, silver was replaced by safer therapies in the recent decades. While silver compounds are still used in external preparations as antiseptics, there has been a growing interest in using the collodial form of silver orally as an alternative medicine. Although no human clinical data support the use of oral colloidal silver, it is being promoted as a cure for AIDS, cancer, and diabetes. Silver is not an essential mineral and does not serve any physiological function in the body. It actually denatures proteins by binding to their reactive groups. It can inactivate some enzymes by forming hemisilver sulfides with sulfhydryl groups of the enzymes (1). Silver when taken orally can interact with and reduce the effectiveness of tetracycline, quinolone, and penicillamine. Long term use can cause silver deposition in the skin and mucous membranes leading to an irreversible condition called argyria, characterized by bluish-gray to gray-black pigmentation (2) (3) (7). Other adverse effects include seizures (6) and kidney damage. Pregnant women should not consume colloidal silver as it can cause developmental abnormalities in the fetus (1).
Purported uses
AIDS
Cancer treatment
Diabetes
Immunostimulation
Infections
Constituents
Silver particles suspended in liquid.
Mechanism of Action
Silver is unstable in suspension form and can bind to proteins. Silver compounds form hemisilver sulfides with sulfhydryl groups that leads to inactivation of enzymes. Silver also has the ability to bind amino, carboxyl, phosphate and imidazole groups
(1). Studies have shown that silver accumulates in rat liver and binds with various tissues and basal membranes. It also affects the activities of lactate dehydrogenase and glutathione peroxidase and the peroxidation of membrane lipids
(4).
Pharmacokinetics
Approximately 10% of silver salts may be absorbed following ingestion, with increased absorption from ruptured mucus membranes and skin wounds. The half-life varies from several days to months but silver deposited in the skin has a much longer half-life. It is excreted into the bile and eliminated in the feces
(1).
Warnings
The Food and Drug Administration (FDA) has issued a consumer advisory about the risk of permanent skin and mucous membrane discoloration known as argyria, associated with use of dietary supplements containing colloidal silver
(7).
Contraindications
Pregnant women should not use colloidal silver as it can cause developmental abnormalities in the fetus
(1).
Adverse Reactions
Reported (Oral): Accumulation of silver in the body causes argyria, a bluish-gray discoloration of the skin, which is untreatable. Other effects include seizures and kidney damage.
Reported (Topical): Topical use of silver nitrate for burns may cause methemoglobinemia.
Exposure to high concentrations of silver, such as in an industrial setting, leads to systemic toxicity
(1) (5).
Herb-Drug Interactions
Antibiotics: Colloidal silver can reduce the bioavailability of antibiotics such as tetracycline and quinolone.
Penicillamine: Colloidal silver can reduce the effectiveness of drugs such as penicillamine by binding to the drug.
Literature Summary and Critique
References
