Skip to content

Colloidal Silver



Silver has a long history of medicinal use and is a recognised and effective antimicrobial. Colloidal silver, which is colloid of silver particles suspended in liquid, has become a popular supplement, but unfortunately many of the claims made about its powers have no scientific backing. That’s not to say it’s ineffective: it can work very well, says naturopath and western herbalist Teresa Mitchell-Paterson, provided you choose the right form, calculate the correct dose, take it for a specific problem for a short period of time rather than using it as a general preventive over the long term.

Question from Selena: I would love a few tips and a basic guideline on how to use colloidal silver: recommend dosages, for how many days, for various ailments such as stuffy nose, tooth pain, earache/infection, sore throat etc. My brand is 20ppm. Selena.

Naturopath and western herbalist Teresa Mitchell-Peterson responds

Silver has been used medically for many centuries both internally and topically, but largely topically. During the late 17th and early 18th century it was used to treat venereal disease, and also – in the form of silver nitrate – to treat ulcers; however, because we don’t know whether these ulcers were varicose ulcers, or created by a bacteria, we can’t determine exactly which bacteria it was treating.

During the 1920s the US Federal Drug Administration (FDA) determined silver possessed some antimicrobial activity. At this point it was still being used topically for ulcers and as an antimicrobial, but was supplanted by penicillin following its discovery in 1940.

The 1960s saw silver return to favour when it was used as a topical treatment for burns, and also in combination with sulphur in a sulphonamide antibiotic. Sulphur, like silver, is both antimicrobial and antibacterial, so it’s not fully clear which mineral is actually doing the job. In 1990 silver was used to treat antibiotic-resistant strains of bacteria, and was also added to catheters to reduce bacterial overgrowth.

Antimicrobial properties

So there’s no question that silver has antimicrobial properties, and that it can be used to inhibit the growth of both aerobic and anaerobic microbes.

While some evidence suggests silver can bind to proteins in bacteria and denature or inactivate them, this research was conducted on the hemi-silver sulphides, so again it’s a question of whether the silver or the sulphate is more effective.

There’s possibility silver helps with fungus, but no evidence exists as to the specific type of fungus it works on. Some people insist – and this is purely folklore – that it’s effective in treating candida albicans and possibly candida overgrowth. Again, no scientific research backs its use in treating viruses.

Colloidal Silver

Colloidal silver – a colloid comprised of silver particles suspended in liquid – comes in three very different formulations:

  • Ionic silver (these solutions may also be known as monatomic silver; silver hydrosol; and covalent silver)
  • Silver protein
  • True colloidal silver (TCS)

The latter is the least prevalent on the market due to the high cost of manufacture, but the most effective as it contains the highest level of silver particles: 50 to 80 percent, with the balance made up of silver ions.

Ionic silver differs from silver particles in that it is missing one electron, something that changes the physical properties of a substance. Silver in ionic form is highly reactive with other elements and easily combines to form compounds: in the body ionic silver immediately combines with chloride to form a compound of silver chloride. This compound will not dissolve in the body and is eventually eliminated through the kidneys. So claims that ionic silver has greater bioavailability are inaccurate as silver ions cannot exist in the human body in their original form.

The other factor here is that the silver particles, not the ions, have been the subject of research.

The high percentage of silver particles in TCS is responsible for its characteristic slightly cloudy, opaque appearance. However, you will notice this only when you open the container as bottles are generally brown or blue.

Some colloidal products contain a sulphur addition called silver sulphadiazine, something people with a sulphur allergy need to be aware of. This adds a yellow tinge to the solution. Concentrations of colloidal silver vary hugely: they can be anything from five parts per million (ppm) to 80ppm. However, higher concentrations do not necessarily equate to a more effective product: evidence clearly suggests the ppm and their effects vary according to the types of bacteria being treated.

How to take colloidal silver

Because silver has no known physiological function in the body and is not an essential mineral, which means we don’t need it on a daily basis, TCS should be taken only for its antibacterial properties.

I see potential problems in self-prescribing given the huge variances in the suggested dosage ranges on the market. As mentioned, the TCS products can be anything from five ppm to 20ppm. Research suggests doses from eight t0 80 miligrams per litre, but this is confusing because how does it relate to parts per million?

The US Environmental Protection Agency (EPA) provides a dosage guideline, called a reference dose, as it recognises the antimicrobial properties of silver. It’s calculated by multiplying your weight in pounds by 12, and dividing the resulting figure by the parts per million of the colloidal silver you use.

So if you weigh 57 kilograms and you have a 10 ppm TCS solution:
57kgs x 2.2 (to convert to pounds) = 125 pounds
125 pounds x 12 = 1500
1500 divided by 10ppm = 150 drops

Generally I say 20 drops is equal to on millilitre, so 150 drops divided by 20 equals 7.5mls, which is one and a half teaspoons daily.

The key with colloidal silver is that it’s not a one-dose treatment: it needs to be taken for a period of time, so I’m going to say one month. However, if you experience no relief from symptoms after a week, whether using it topically or internally, you need to seek a practitioner’s advice: colloidal silver should not take the place of an antibiotic treatment where needed.


  • Colloidal silver is definitely not a prevention or cure for the shopping list of diseases some marketing hype would have you believe.
  • It doesn’t suit everyone, as some people actually have a genetic resistance to silver treatment.
  • Some people are allergic to silver, so it’s a good idea to check with a skin scratch test before using it.
  • Long-term use can result in argyria, an accumulation of silver that can cause a bluish discolouration of the skin. This is actually the origin of the term “blue bloods” as in centuries past only the wealthy used silver medicinally.
  • Kidney damage is another risk with taking colloidal silver in too high a dose for too long a time.
  • It should not be used during pregnancy because it effect on the foetus is unknown. While it apprently does not cross the blood-brain barrier, it’s unknown whether it crosses the placental barrier.

So broadly my advice is, if you are going to take colloidal silver, be cautious, Buy only true colloidal silver; calculate your dose using the EPA guidelines; and if it’s not working, use something else.

One last point: if ongoing health issues have prompted you to use colloidal silver, consider consulting a natural health practitioner who can possibly prescribe more specific herbs or nutrients for the condition.

More about the author