Silver in Wound Care: Silver Based Wound Dressings

Let's initially keep it simple and to the point by not talking about positive and negative isotopes etc. Silver impregnated wound dressings release silver ions at the wound surface which kill bacteria. Because of the antimicrobial properties infection is decreased and healing promoted.

In wound care, silver is utilized in several formulations such as silver sulfadiazine, alginate, and nitrate.

Hippocrates, commonly referred to as the "father of medicine" wrote that silver has beneficial healing and anti-disease properties. The Greeks used silver jars to keep water and other beverages fresh. Some of us might remember our parents or grandparents putting silver coins in milk bottles to keep the milk fresh longer.

Modern science demonstrates that silver ions are relatively effective in fighting off bacteria (germicidal effect) including MRSA and VRE and even viruses, fungi, and parasites. Silver ions seem to have certain advantages over regular antibiotics because the bacteria can't develop resistance.

On the other hand are there the studies and clinical trials showing side effects. Silver is toxic and prolonged used may cause detrimental effects such as skin irritation up to even damaging skin tissue.

My conclusion: All these things considered I conclude that silver can be a lifesaver in some circumstances. When other measures don't work it can help treat presumably untreatable conditions. But with its side effects/ downsides in mind it should be used carefully, sporadically, and, in my opinion, after weighing other options that may be more natural.

Picture by Mdd | Wikimedia Commons

According to this article on topical antimicrobial agents Silver nitrate is no longer widely used as a wound care methodology. Also discolored skin and irritation associated with the use of silver nitrate are reported. Despite these findings silver nitrate applicators are still used widely.

Silver sulphadiazine (SSD) and silver releasing dressings remain popular.

Silver sulfadiazine prevents the growth of a wide array of bacteria, as well as yeast, on the damaged skin. It is a topical antibacterial historically used as a burn cream on second- and third-degree burns.

Opinions on this topical agent differ considerably.

Some studies have found that it increased healing times and is therefore no longer recommended. Source: silver sulfadiazine wiki

Other studies however demonstrated that silver sulfadiazine helped wounds heal far better than for example povidone-iodine and bacitracin. Source: PubMed

Until 2009 there hadn't really been any substantial clinical research demonstrating the efficiency of silver releasing wound and burn dressings. Conclusion of a meta analysis conducted in 2009 was that there is efficacy but more research should be conducted.

"This meta-analysis confirms the effectiveness of silver dressings in wound healing and improving patients' quality of life. However, it also highlights the need for additional well-designed randomized controlled trials to evaluate the effectiveness of silver-related dressings further."
Source: PubMed

Picture licensed under Creative Commons.

Some researchers have concluded that silver has a negative effect on the migration and the shape of skin cells. There are examples where, after prolonged topical use, silver actually delayed the wound healing process.

More recently silver is thought to have so called cytotoxic activity. This means the body's own skin cells (host cells) may be affected negatively. Skin cells deformed and one particular source mentions that after 3 weeks keratinocytes and fibroblasts were all eliminated. More on this on burnsjournal.com

In one study the researchers examined the cytotoxic effects of silver on keratinocytes (the predominant cell type (95%) in the epidermis which is the outer layer of the human skin,) and fibroblasts (play a critical role in wound healing and connective tissue).

"These results suggest that consideration of the cytotoxic effects of silver and silver-based products should be taken when deciding on dressings for specific wound care strategies." More on this study here: PubMed

There is this experimental study on the effects of topical components on burn wounds in Yorkshire pigs. A comparison was made between honey and silver sulfadiazine, and between honey and sugar.

Regrowth of skin (epithelialization) was achieved within 21 days with honey and sugar whereas it took 28 - 35 days with silver sulfadiazine.

Furthermore: The creation of new tissue during the wound healing process (granulation "was clearly seen to be suppressed initially by treatment with silver sulfadiazine."

And: There was less inflammation in laboratory samples of honey-treated wounds than those treated with sugar and silver sulfadiazine. The report also mentions a rather technical process indicating: "a more advanced stage of healing." (this process (actin staining) was diminished which benefits certain body cells called myofibroblasts)

Conclusion of this study:

"There is much anecdotal evidence to support its use, and randomised controlled clinical trials that have shown that honey is more effective than silver sulfadiazine for the treatment of burns."

"Argyria is more often associated with the consumption of colloidal silver solutions than with silver nitrate, especially at the extremely low concentrations present for the disinfection of water. However, it is still important to consider before ingesting any sort of silver-ion solution."
Source: Wikipedia

Commonly known is the so called Blue Man. His skin has turned purple, blue, silver-ish which is a known complication of chronic use of colloidal silver.

More on why useless remedies with significant side effects such as colloidal silver seem to persist in this in-depth article.