What Is Colloidal Silver?

Is the natural remedy safe or dangerous?

Marketed as a remedy for a range of health problems, colloidal silver is a solution of tiny silver particles suspended in a liquid base. It’s typically taken orally, but some products are sprayed, applied to the skin, or injected into a vein.

Silver had been used in medicine for centuries, touted as a cure-all for everything from tuberculosis and arthritis to herpes and cancer. Even today, many alternative practitioners believe that colloidal silver offers health benefits by supporting immune function and preventing or treating infections, both common and severe.

side effects of colloidal silver

Verywell / Laura Porter

Despite claims to the contrary, colloidal silver has no known function in the body. In fact, the Food and Drug Administration (FDA) ruled in 1999 that these colloidal silver products were neither safe nor effective and sued a number of manufacturers over false health claims.

While many colloidal silver products were removed from drugstore shelves following the FDA ruling, they have since been rebranded as dietary supplements or homeopathic remedies, neither of which require FDA approval.

What Is Colloidal Silver Used For?

Manufacturers of colloidal silver often broadly claim that their products are capable of stimulating the immune system and helping the body heal itself. Proponents believe that the supplement can aid in wound healing, improve skin disorders, and either prevent or treat diseases like the flu, pneumonia, herpes, eye infections, shingles, cancer, and AIDS.

Many of these claims have been supported by test tube studies in which colloidal silver has been shown to exert powerful antibacterial, antiviral, antifungal, and anti-inflammatory effects. What the studies fail to show is what happens outside of the test tube.

When ingested, colloidal silver has the potential to cause toxicity and, in rare cases, death. Moreover, there remains little evidence that silver exerts the same antimicrobial properties when internalized.

Ultimately, the human body has no need for silver. It is not an essential mineral and serves no biological function of any sort.

While silver toxicity is rare, silver can accumulate in the body over months and years. This can lead to severe disfigurement and potentially harmful deposits in the liver, spleen, kidney, muscle, and brain, according to research from Imperial College in London.

That is not to say that silver offers no health benefits. When used topically (on the skin), colloidal silver can aid in healing and prevent infection.

Wound Healing

A number of studies have investigated the use of silver-containing dressings on skin ulcers and wounds. Many of these have found that the silver particles exerted antibacterial properties that aid the treatment of diabetic ulcers, skin grafts, bed sores, necrotizing fasciitis, and other serious skin injuries.

A 2018 study from Iran concluded that a topical ointment containing silver nanoparticles was able to reduce skin inflammation during healing and speed the regrowth of skin compared to people provided a placebo.

This suggests that the short-term, topical use of silver-containing products have their place in treatment.

Possible Side Effects

People who take colloidal silver may not experience any immediate side effects. The concerns are related more to the long-term consequences of colloidal silver use as particles gradually accumulate and embed themselves in organs and tissues, most especially the skin.

Over time, this can lead to a permanent, disfiguring condition called argyria in which tissues take on a bluish-gray discoloration. The gums are usually first affected, followed by the skin, eyes, nails, and deeper tissue layers. Headache, fatigue, and myoclonic seizures may also occur.

Although it is unclear what toxicity silver poses to internal organs, animal studies have shown that inordinately high levels can interfere with kidney and liver function, damage the central nervous system, and instigate the release of calcium from bones.

It is not known how silver affects reproduction or pregnancy, but research issued by the National Toxicology Program suggests that silver does not cause cancer.

There have been several deaths linked with colloidal silver use, including one case report published in Neurology in which a 71-year-old man died after taking a daily dose of colloidal silver for four months.

Drug Interactions

In addition to potential health hazards, colloidal silver is known to interact with a number of medications, either by reducing their effectiveness, increasing side effects, or impairing liver function as the drug is metabolized.

Possible interactions include:

  • Antiarrhythmic drugs like Cordarone (amiodarone)
  • Antifungals like Diflucan (fluconazole) and Sporanox (itraconazole)
  • Levothyroxine, used to treat thyroid problems
  • Methotrexate, used to treat autoimmune disorders
  • Penicillamine, used to treat rheumatoid arthritis
  • Quinolone antibiotics, including Cipro (ciprofloxacin) and Penetrex (enoxacin)
  • Statin drugs like Pravachol (pravastatin) and Zocor (simvastatin)
  • Tetracycline antibiotics, including Achromycin (tetracycline) and Minocin (minocycline)
  • Tylenol (acetaminophen)

Other drug interactions are possible, so advise your healthcare provider if you are taking colloidal silver, even for short-term use.

Dosage and Preparation

There is no safe dose of colloidal silver. Moreover, it is not known at what point silver toxicity may occur. Part of the problem is that the concentration of silver particles can vary from one brand to the next. Some contain as few as 15 parts per million (ppm), while others are in excess of 500 ppm. Age, weight, and health status can also play a part.

Despite the FDA ruling against their safety, colloidal silver products are still available as dietary supplements. Most are sold in liquid form. There are even colloidal silver generators you can buy that diffuse silver particles into water. Colloidal silver soaps, mouthwash, eye drops, body lotions, lozenges, and nasal sprays are also available.

What to Look For

It is important to remember that dietary supplements are not required to undergo the research or safety testing that pharmaceutical drugs do. As such, quality can vary considerably from one manufacturer to the next.

Unlike vitamin supplements, few colloidal silver products are voluntarily submitted for evaluation by an independent certifying authority like U.S. Pharmacopeia (USP), ConsumerLab, or NSF International. As such, the consumer can be left blind as to what the product contains or how safe it is.

If you decide to buy a colloidal silver product, even for short-term use, choose those that clearly indicate the concentration in parts per million (ppm) on the product label (remembering that less is more).

Do not be swayed by any unsupported health claims. In the end, colloidal silver has no known benefit when ingested, injected, or inhaled, and it may cause more harm than good.

Frequently Asked Questions

  • Is it illegal to include colloidal silver in products?

    It’s not illegal to put colloidal silver in products. However, products can't make any claims that colloidal silver has any medicinal benefits. The FDA ruled that colloidal silver isn’t safe or effective in treating any illness. But the FDA doesn’t tightly regulate supplements or homeopathic products. Colloidal silver is still used in those unregulated products.

  • Can colloidal silver help treat COVID?

    There has been some early research indicating that silver nanoparticles may be able to help prevent COVID infection. More research is needed, though. Even if there was a definite benefit, it would need to be weighed against the known risks of colloidal silver.

  • Is it okay to use skin creams with silver?

    Topical products (products used on the skin) that have colloidal silver may have some benefits. For instance, bandages and dressings with colloidal silver may help with burns, skin infections, or skin wounds. You should talk to your doctor before using these types of products.

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10 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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