Since the days of antiquity, humans have been throwing coins into water sources such as a well or fountain. Why? Well, wish making hasn't always been the motivation. One theory is that the antibacterial properties of silver were known, and this was done to make water safer to drink. These days, there is growing evidence that silver may also have many other health benefits, especially in the colloidal form, a solution in which silver nanoparticles are suspended in water.

Colloidal silver has become increasingly popular over the last few decades, but the health benefits of silver have been utilized for a millennium. The first believed use of silver for medical purposes was almost over 2,000 years ago—Hippocrates is said to have used silver to heal skin ulcers and wounds. During the 4th century, it was used by the Egyptians, and in 980 AD,  Avicenna used silver to purify blood as well as treat heart palpitations and bad breath. In the 14th century,  Conrad von Megenberg noted in Book of Nature that silver “slag”, when applied topically, could be used to treat scabies and bleeding hemorrhoids. 

Hahnemann (1755-1843), the founder of homeopathic medicine, also used silver to treat medical conditions, including silver nitrate to help stop bleeding. Silver nitrate is still used today by doctors to stop mild bleeding after a dermatological procedure. However, if silver is taken in excess, a person’s skin can become blue in color, a condition doctors call argyria.   

Prior to the advent of antibiotics, colloidal silver was a common treatment for infections. This therapy fell out of favor until the 1990s, when the risk of antibiotic resistance starting becoming a concern for many healthcare professionals. 

How does colloidal silver work?

It is believed that silver nano-molecules enter bacteria and attach to certain bacteria proteins, causing them to change structure (denature) and become non-functional. Silver is also believed to bind to certain enzymes in viruses, fungi, and parasites, making them inactive.

Here are some possible benefits of colloidal silver:  


Since the advent of antibiotics in the 1940s, bacteria have become cleverer and have developed mechanisms to help protect themselves from antibiotic drugs. Bacteria form a type of “force shield” to protect themselves against the drugs designed to kill them—scientists call this shield a "biofilm".  A 2014 study showed that colloidal silver could help disrupt the force shield that certain bacteria, like Staphylococcus aureus, creates. In addition, a 2011 study showed that silver particles could destroy bacteria directly by destroying their cell walls. A strong cell well is crucial for bacteria to reproduce.  According to a 2018 study, silver may also kill some of the good bacteria in the gut so use of a probiotic should be considered if silver is taken routinely. 


Viruses are infectious agents for which modern medicine has limited treatment. The common cold still does not have a cure while medications that fight influenza simply reduce the amount of time one is ill by about one day. Antiviral alternatives are sought by many. A 2005 study in Journal of Nanobiotechnology showed silver could stop the HIV virus from binding to host cells. A 2013 study of the herpes virus showed that silver nanoparticles could also make the herpes virus less infectious. Silver has also been studied against other viruses. While these studies provide some hope for future treatments, colloidal silver should not be used as a method to prevent HIV or herpes infections. 


Fungi are all around us. Some can be helpful and consumed as a food, like a mushroom. Others, however, can cause infection due to their overgrowth. Balance is the key. A 2016 study showed that silver had anti-fungal properties when tested at various concentrations. 

Dental cavities

There are a few studies that suggest that colloidal silver may be helpful in the prevention of tooth cavities and reduce the risk of infection in those undergoing dental implants. Swishing a colloidal silver and water mixture in the mouth can be considered.

Wound healing/skin burns

Chronic wounds due to diabetes or burns present challenges for both patients and caretakers alike. Finding the best topical medication to apply is crucial to not only preventing infection but also to help speed up the healing process. A 2006 study concluded that silver “can be used on second-degree burn wounds and can decrease the risk of wound infection and speed up wound healing”.  A 2009 study supported the use of silver in helping to heal second-degree skin burns. Topical silver salves are available for use.

Sinus health

Millions of people worldwide visit their doctors each year with complaints related to their sinuses, a term commonly used to describe what doctors refer to as paranasal sinuses. Hollow “caves” in the human skull, which are essentially absent in newborns but develop fully by around age eight, sinuses reach their full adult size by puberty. 

Specific food avoidance, medications, mineralsvitaminsessential oils, and homeopathic remedies can all be considered as options to help one prevent allergies, nasal congestion, and ultimately infections of the sinus tract. Maintaining good sinus health is crucial to overall health and well-being. Use of colloidal silver spray for sinus infection prevention is sometimes used, with many claiming benefits. Some studies have shown potential benefit. However, studies proving overall effectiveness are lacking. 

Sinus inflammation was not improved in a small 2017 study of 22 patients who use colloidal silver to help ease their sinus issues. More studies are needed before use of colloidal silver can be recommended for sinus infections and/or prevention. Learn more about other methods to maintain sinus health

Silver used in hospitals

Urinary infections are a common hospital infection, especially when a Foley catheter is used to help one urinate. A 2017 study showed that silver-lined Foley urine catheters could prevent urine infections. Similarly, a 2017 study showed that certain intravenous (IV) tubing, when lined with silver, resulted in less bacterial infections in patients who were in the intensive care unit. Another study from the same study showed that yeast infections were also reduced in those with silver-lined intravenous (IV) catheters.

Silver toxicity

The maximum dose in total daily silver intake should not exceed 14 mcg/kg daily. Never take more than is recommended on the label of the product used. Rarely, when silver levels become elevated in the skin, an irreversible bluish-gray skin color called argyria can result. Most cases reported of this condition did not involve colloidal silver but involved homemade silver salts.  Further, it should be noted that the Federal Drug Administration (FDA) does not consider colloidal silver to be safe. However, many advocates cite its long history of safety when used conservatively. 

Can silver be used during pregnancy?

No studies have shown any harms, but it is probably best to avoid use during pregnancy and during breastfeeding unless your healthcare provider advises you otherwise.

Are there medication interactions?  

Taking colloidal silver at the same time as certain medications can reduce absorption of the medications. These include antibiotics and the thyroid medication levothyroxine. However, no drug interaction is known.

Suggested doses for adults: 


  • Topical silver salve - use as directed
  • Colloidal silver can also be applied to the skin and wounds

Oral Dosing

The dosing  guidelines below are  recommended in  the 2013 book titled Colloidal SilverThe Natural Antibiotic

  • Low dosage:  3-5 ppm once or twice per day for preventive purposes
  • Moderate dosage:  25-30 ppm two to three times per day for up to two weeks  for bacterial and viral infections
  • High dose: 100 ppm once per day for up to seven days for fungal infections

* Taking more than 200 ppm is not advised, especially if taken for more than five days.

* For children, one-half the dose is usually advised. Check with your child's physician before administering. 

Note: Due to silver’s antibacterial properties, when taken for long periods of time, beneficial bacteria in the gut may be affected. Taking probiotics should also be considered to help counteract this effect.  


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