Medical uses of silver
|Medical uses of silver|
Silver is added to some bandages for its antimicrobial effect.
The medical uses of silver include its use in wound dressings, creams, and as an antibiotic coating on medical devices. Wound dressings containing silver sulfadiazine or silver nanomaterials may be used on external infections. There is tentative evidence that silver coatings on endotracheal breathing tubes may reduce the incidence of ventilator-associated pneumonia.
Silver generally has low toxicity, and minimal risk is expected when silver is used in approved medical applications. Alternative medicine products such as colloidal silver are not safe or effective.
Mechanism of action
Silver and most silver compounds have an oligodynamic effect and are toxic for bacteria, algae, and fungi in vitro. The antibacterial action of silver is dependent on the silver ion. The effectiveness of silver compounds as an antiseptic is based on the ability of the biologically active silver ion (Ag+
) to irreversibly damage key enzyme systems in the cell membranes of pathogens. The antibacterial action of silver has long been known to be enhanced by the presence of an electric field. Applying an electric current across silver electrodes enhances antibiotic action at the anode, likely due to the release of silver into the bacterial culture. The antibacterial action of electrodes coated with silver nanostructures is greatly improved in the presence of an electric field.
Silver, used as a topical antiseptic, is incorporated by bacteria it kills. Thus dead bacteria may be the source of silver which may kill additional bacteria.
Systemic reviews in 2014, 2017 and 2018 concluded that more modern dressings, with and without silver, show better results for wound healing and infection prevention than silver sulfadiazine (SSD).
The US Food and Drug Administration has approved a number of topical preparations of silver sulfadiazine for treatment of second- and third-degree burns.
A 2018 Cochrane review found that silver-containing dressings may increase the probability of healing for venous leg ulcers. A 2012 systematic review found that silver-containing dressings were no better than non-silver-containing dressings in treating burns. A 2012 Cochrane review found that silver-containing hydrocolloid dressings were no better than standard alginate dressings in treating diabetic foot ulcers. A 2010 Cochrane review found insufficient evidence to determine if dressings containing silver increase or decrease infection or affect healing rates. Another 2010 review found some evidence that silver-impregnated dressings improve the short-term healing of wounds and ulcers. The lead author of this paper is a speaker for one of the manufacturers of one of the silver dressings under study. A 2009 systematic review found that silver dressings improve both wound healing and quality of life when managing chronic non-healing wounds. Another 2009 review concluded that the evidence for silver-containing foam in chronic infected wounds is not clear, but found that silver-containing foam resulted in a greater reduction in wound size and more effective control of leakage and odor than non-silver dressings. A Cochrane review from 2013 found that all of the trials that assessed dressings on superficial and partial thickness burn wounds were at risk of bias and the data were poorly reported. Silver sulphadiazine had consistently poorer healing outcomes and delayed healing times compared with biosynthetic, silicon-coated and silver dressings. Another systematic review concluded that the evidence shows an overall positive effect of silver-releasing dressings in the management of infected chronic wounds, but expressed concern that the quality of the underlying trials was limited and potentially biased.
Limited evidence suggests that endotracheal breathing tubes coated with silver may reduce the incidence of ventilator associated pneumonia (VAP) and delay its onset, although no benefit is seen in the duration of intubation, the duration of stay in intensive care or the mortality rate. Concerns have been raised surrounding the unblinded nature of some of the studies. It is unknown if they are cost effective, and more high quality scientific trials are needed.
Evidence does not support an important reduction in the risk of urinary tract infections when silver-alloy catheters are used. These catheters are associated with greater cost than other catheters.
A combination of chlorhexidine & silver-sulfadiazine used in central venous catheters (CVC) reduces the rate of catheter-related bloodstream infections. However, it seems difficult to discern whether the addition of silver-sulfadizine is responsible for the antimicrobial action of chlorhexidine-silver-sulfadiazine central venous catheters. As chlorhexidine alone may be the main cause of the antimicrobial action and more studies are needed in order to resolve this. Although, it has been hypothesized silver-sulfadizine may still help reduce infection through another, not yet determined, mechanism.
Conjugations with existing drugs
Research in 2018 into the treatment of central nervous system infections caused by free-living amoebae such as Naegleria fowleri and Acanthamoeba castellanii, tested the effectiveness of existing drugs as well as the effectiveness of the same drugs when they were conjugated with silver nanoparticles. In vitro tests demonstrated more potent amoebicidal effects for the drugs when conjugated with silver nanoparticles as compared to the same drugs when used alone. They also found that conjugating the drugs with silver nanoparticles enhanced their anti-acanthamoebic activity. 
Silver-halide imaging plates used with X-ray imaging were the standard before digital techniques arrived. Silver x-ray film remains popular for its accuracy, and cost effectiveness, particularly in developing countries, where digital X-ray technology is usually not available.
Silver compounds have been used in external preparations as antiseptics, including both silver nitrate and silver proteinate, which can be used in dilute solution as eyedrops to prevent conjunctivitis in newborn babies. Silver nitrate is also sometimes used in dermatology in solid stick form as a caustic ("lunar caustic") to treat certain skin conditions, such as corns and warts.
Silver nitrate is also used in certain laboratory procedures to stain cells. As it turns them permanently a dark-purple/black color, in doing so increasing individual cells' visibility under a microscope and allowing for differentiation between cells, or identification of irregularities. Silver is also used in bone prostheses, reconstructive orthopedic surgery, and cardiac devices. Silver diamine fluoride appears to be an effective intervention to reduce dental caries (tooth decay). Silver is also a component in dental amalgam.
Silver acetate has been used as a potential aid to help stop smoking; a review of the literature in 2012, however, found no effect of silver acetate on smoking cessation at a six-month endpoint and if there is an effect it would be small. Silver has also been used in cosmetics, intended to enhance antimicrobial effects and the preservation of ingredients.
In the 1840s, founder of gynecology J. Marion Sims employed silver wire, which he had a jeweler fashion, as a suture in gynecological surgery. This produced very favorable results when compared with its predecessors, silk and catgut.
Though toxicity of silver is low, the human body has no biological use for silver and when inhaled, ingested, injected, or applied topically, silver will accumulate irreversibly in the body, particularly in the skin, and chronic use combined with exposure to sunlight can result in a disfiguring condition known as argyria in which the skin becomes blue or blue-gray. Localized argyria can occur as a result of topical use of silver-containing creams and solutions, while the ingestion, inhalation, or injection can result in generalized argyria. Preliminary reports of treatment with laser therapy have been reported. These laser treatments are painful and general anesthesia is required. A similar laser treatment has been used to clear silver particles from the eye, a condition related to argyria called argyrosis. The Agency for Toxic Substances and Disease Registry (ATSDR) describes argyria as a "cosmetic problem".
One of the more publicized incidents of argyria came in 2008, when a man named Paul Karason, whose skin turned blue from using colloidal silver for over 10 years to treat dermatitis, appeared on NBC's "Today" show. Karason died in 2013 at the age of 62 after a heart attack.
Colloidal silver may interact with some prescription medications, reducing the absorption of some antibiotics and thyroxine, among others.
Some people are allergic to silver, and the use of treatments and medical devices containing silver is contraindicated for such people. Although medical devices containing silver are widely used in hospitals, no thorough testing and standardization of these products has yet been undertaken.
Electrolytically-dissolved silver has been used as a water disinfecting agent, for example, the drinking water supplies of the Russian Mir orbital station and the International Space Station. Many modern hospitals filter hot water through copper-silver filters to defeat MRSA and legionella infections.:29 The World Health Organization includes silver in a colloidal state produced by electrolysis of silver electrodes in water, and colloidal silver in water filters as two of a number of water disinfection methods specified to provide safe drinking water in developing countries. Along these lines, a ceramic filtration system coated with silver particles has been created by Ron Rivera of Potters for Peace and used in developing countries for water disinfection (in this application the silver inhibits microbial growth on the filter substrate, to prevent clogging, and does not directly disinfect the filtered water).
Alternative medicine 
A bottle of colloidal silver
|Risks||Argyria, decreased drug absorption,|
|Legality||Not to be sold for consumption or for disinfection in Sweden. Not to treat or prevent cancer (UK, Sweden, etc.)|
Colloidal silver (a colloid consisting of silver particles suspended in liquid) and formulations containing silver salts were used by physicians in the early 20th century, but their use was largely discontinued in the 1940s following the development of safer and effective modern antibiotics. Since about 1990, there has been a resurgence of the promotion of colloidal silver as a dietary supplement, marketed with claims of it being an essential mineral supplement, or that it can prevent or treat numerous diseases, such as cancer, diabetes, arthritis, HIV/AIDS, herpes, and tuberculosis. No medical evidence supports the effectiveness of colloidal silver for any of these claimed indications. Silver is not an essential mineral in humans; there is no dietary requirement for silver, and hence, no such thing as a silver "deficiency". There is no evidence that colloidal silver treats or prevents any medical condition, and it can cause serious and potentially irreversible side effects such as argyria.
In August 1999, the U.S. FDA banned colloidal silver sellers from claiming any therapeutic or preventive value for the product, although silver-containing products continue to be promoted as dietary supplements in the U.S. under the looser regulatory standards applied to supplements. The FDA has issued numerous Warning Letters to Internet sites that have continued to promote colloidal silver as an antibiotic or for other medical purposes. Despite the efforts of the FDA, silver products remain widely available on the market today. A review of websites promoting nasal sprays containing colloidal silver suggested that information about silver-containing nasal sprays on the internet is misleading and inaccurate.
In 2002, the Australian Therapeutic Goods Administration (TGA) found there were no legitimate medical uses for colloidal silver and no evidence to support its marketing claims. The U.S. National Center for Complementary and Integrative Health (NCCIH) warns that marketing claims about colloidal silver are scientifically unsupported, that the silver content of marketed supplements varies widely, and that colloidal silver products can have serious side effects such as argyria. In 2009, the USFDA issued a "Consumer Advisory" warning about the potential adverse effects of colloidal silver, and said that "...there are no legally marketed prescription or over-the-counter (OTC) drugs containing silver that are taken by mouth." Quackwatch states that colloidal silver dietary supplements have not been found safe or effective for the treatment of any condition. Consumer Reports lists colloidal silver as a "supplement to avoid", describing it as "likely unsafe". The Los Angeles Times stated that "colloidal silver as a cure-all is a fraud with a long history, with quacks claiming it could cure cancer, AIDS, tuberculosis, diabetes, and numerous other diseases."
It may be illegal to market as preventing or treating cancer, and in some jurisdictions illegal to sell colloidal silver for consumption. In 2015 an English man was prosecuted and found guilty under the Cancer Act 1939 for selling colloidal silver with claims it could treat cancer.
Hippocrates in his writings discussed the use of silver in wound care. At the beginning of the twentieth century surgeons routinely used silver sutures to reduce the risk of infection. In the early 20th century, physicians used silver-containing eyedrops to treat ophthalmic problems, for various infections, and sometimes internally for diseases such as tropical sprue, epilepsy, gonorrhea, and the common cold. During World War I, soldiers used silver leaf to treat infected wounds.
Prior to the introduction of modern antibiotics, colloidal silver was used as a germicide and disinfectant. With the development of modern antibiotics in the 1940s, the use of silver as an antimicrobial agent diminished. Silver sulfadiazine (SSD) is a compound containing silver and the antibiotic sodium sulfadiazine, which was developed in 1968.
The National Health Services in the UK spent about £25 million on silver-containing dressings in 2006. Silver-containing dressings represent about 14% of the total dressings used and about 25% of the overall wound dressing costs.
Concerns have been expressed about the potential environmental cost of manufactured silver nanomaterials in consumer applications being released into the environment, for example that they may pose a threat to benign soil organisms.
- Maillard JY, Hartemann P (November 2013). "Silver as an antimicrobial: facts and gaps in knowledge". Critical Reviews in Microbiology. 39 (4): 373–83. doi:10.3109/1040841X.2012.713323. PMID 22928774.
- Medici S, Peana M, Crisponi G, Nurchi VM, Lachowicz JI, Remelli M, Zoroddu MA (2016). "Silver coordination compounds: A new horizon in medicine". Coordination Chemistry Reviews. 327-8: 349–359. doi:10.1016/j.ccr.2016.05.015.
- Atiyeh BS, Costagliola M, Hayek SN, Dibo SA (March 2007). "Effect of silver on burn wound infection control and healing: review of the literature". Burns. 33 (2): 139–48. doi:10.1016/j.burns.2006.06.010. PMID 17137719.
- Qin Y (June 2005). "Silver-containing alginate fibres and dressings". International Wound Journal. 2 (2): 172–6. doi:10.1111/j.1742-4801.2005.00101.x. PMID 16722867.
- Hermans MH (December 2006). "Silver-containing dressings and the need for evidence". The American Journal of Nursing. 106 (12): 60–8, quiz 68–9. doi:10.1097/00000446-200612000-00025. PMID 17133010.
- Bouadma L, Wolff M, Lucet JC (August 2012). "Ventilator-associated pneumonia and its prevention". Current Opinion in Infectious Diseases. 25 (4): 395–404. doi:10.1097/QCO.0b013e328355a835. PMID 22744316.
- Lansdown AB (2006). "Silver in Health Care: Antimicrobial Effects and Safety in Use". Biofunctional Textiles and the Skin. Current Problems in Dermatology. 33. pp. 17–34. doi:10.1159/000093928. ISBN 978-3-8055-8121-9. PMID 16766878.
- "Over-the-Counter Drug Products Containing Colloidal Silver Ingredients or Silver Salts". FDA. August 17, 1999. Retrieved 18 August 2016.
- Spadaro JA, Berger TJ, Barranco SD, Chapin SE, Becker RO (November 1974). "Antibacterial effects of silver electrodes with weak direct current". Antimicrobial Agents and Chemotherapy. 6 (5): 637–42. doi:10.1128/AAC.6.5.637. PMC 444706. PMID 15825319.
- Akhavan O, Ghaderi E (February 2009). "Enhancement of antibacterial properties of Ag nanorods by electric field". Science and Technology of Advanced Materials. 10 (1): 015003. doi:10.1088/1468-6996/10/1/015003. PMC 5109610. PMID 27877266.
- Wakshlak RB, Pedahzur R, Avnir D (April 2015). "Antibacterial activity of silver-killed bacteria: the "zombies" effect". Scientific Reports. 5: 9555. doi:10.1038/srep09555. PMC 5386105. PMID 25906433.
- Rashaan ZM, Krijnen P, Klamer RR, Schipper IB, Dekkers OM, Breederveld RS (2014). "Nonsilver treatment vs. silver sulfadiazine in treatment of partial-thickness burn wounds in children: a systematic review and meta-analysis". Wound Repair and Regeneration. 22 (4): 473–82. doi:10.1111/wrr.12196. PMID 24899251.
- Nherera LM, Trueman P, Roberts CD, Berg L (August 2017). "A systematic review and meta-analysis of clinical outcomes associated with nanocrystalline silver use compared to alternative silver delivery systems in the management of superficial and deep partial thickness burns". Burns. 43 (5): 939–948. doi:10.1016/j.burns.2017.01.004. PMID 28161149.
- Nímia HH, Carvalho VF, Isaac C, Souza FÁ, Gemperli R, Paggiaro AO (June 2018). "Comparative study of Silver Sulfadiazine with other materials for healing and infection prevention in burns: A systematic review and meta-analysis". Burns. doi:10.1016/j.burns.2018.05.014. PMID 29903603.
- "Drugs@FDA". Accessdata.fda.gov. Retrieved 2010-07-10.
- Norman G, Westby MJ, Rithalia AD, Stubbs N, Soares MO, Dumville JC (June 2018). "Dressings and topical agents for treating venous leg ulcers" (Full text). The Cochrane Database of Systematic Reviews. 6: CD012583. doi:10.1002/14651858.CD012583.pub2. PMID 29906322.
- Aziz Z, Abu SF, Chong NJ (May 2012). "A systematic review of silver-containing dressings and topical silver agents (used with dressings) for burn wounds". Burns. 38 (3): 307–18. doi:10.1016/j.burns.2011.09.020. PMID 22030441.
- Dumville JC, O'Meara S, Deshpande S, Speak K (June 2013). "Alginate dressings for healing diabetic foot ulcers". The Cochrane Database of Systematic Reviews (6): CD009110. doi:10.1002/14651858.CD009110.pub3. PMID 23799857.
- Storm-Versloot MN, Vos CG, Ubbink DT, Vermeulen H (March 2010). "Topical silver for preventing wound infection". The Cochrane Database of Systematic Reviews (3): CD006478. doi:10.1002/14651858.CD006478.pub2. PMID 20238345.
- Carter MJ, Tingley-Kelley K, Warriner RA (October 2010). "Silver treatments and silver-impregnated dressings for the healing of leg wounds and ulcers: a systematic review and meta-analysis". Journal of the American Academy of Dermatology. 63 (4): 668–79. doi:10.1016/j.jaad.2009.09.007. PMID 20471135.
- Lo SF, Chang CJ, Hu WY, Hayter M, Chang YT (March 2009). "The effectiveness of silver-releasing dressings in the management of non-healing chronic wounds: a meta-analysis". Journal of Clinical Nursing. 18 (5): 716–28. doi:10.1111/j.1365-2702.2008.02534.x. PMID 19239539.
- Beam JW (2009). "Topical silver for infected wounds". Journal of Athletic Training. 44 (5): 531–3. doi:10.4085/1062-6050-44.5.531. PMC 2742464. PMID 19771293.
- Wasiak J, Cleland H, Campbell F, Spinks A (March 2013). "Dressings for superficial and partial thickness burns". The Cochrane Database of Systematic Reviews (3): CD002106. doi:10.1002/14651858.CD002106.pub4. PMID 23543513.
- Lo SF, Hayter M, Chang CJ, Hu WY, Lee LL (August 2008). "A systematic review of silver-releasing dressings in the management of infected chronic wounds". Journal of Clinical Nursing. 17 (15): 1973–85. doi:10.1111/j.1365-2702.2007.02264.x. PMID 18705778.
- Ethicon, Inc. 510(k) Summary for K022483 Feb. 3, 2003
- Argentum Medical LLC 510(k) Summary for K023609 Jan 17, 2003
- Euromed, Inc. 510(k) Summary for K050032 May 17, 2005
- Kinetic Concepts, Inc. 510(k) Summary for K053627 Feb. 6, 2006
- Hunter JD (May 2012). "Ventilator associated pneumonia". BMJ. 344: e3325. doi:10.1136/bmj.e3325. PMC 2563696. PMID 22645207.
- Li X, Yuan Q, Wang L, Du L, Deng L (February 2012). "Silver-coated endotracheal tube versus non-coated endotracheal tube for preventing ventilator-associated pneumonia among adults: a systematic review of randomized controlled trials". Journal of Evidence-Based Medicine. 5 (1): 25–30. doi:10.1111/j.1756-5391.2012.01165.x. PMID 23528117.
- Kane T, Claman F (2012). "Silver tube coatings in pneumonia prevention". Nursing Times. 108 (36): 21–3. PMID 23035371.
- "FDA Clears Silver-Coated Breathing Tube For Marketing". 2007-11-08. Archived from the original on November 14, 2007.
- Lam TB, Omar MI, Fisher E, Gillies K, MacLennan S (September 2014). "Types of indwelling urethral catheters for short-term catheterisation in hospitalised adults". The Cochrane Database of Systematic Reviews (9): CD004013. doi:10.1002/14651858.CD004013.pub4. PMID 25248140.
- Coppin-Raynal E, Le Coze D (October 1982). "Mutations relieving hypersensitivity to paromomycin caused by ribosomal suppressors in Podospora anserina". Genetical Research. 40 (2): 149–64. doi:10.1017/s0016672300019029. PMID 7152256.
- Choi YJ, Lim JK, Park JJ, Huh H, Kim DJ, Gong CH, Yoon SZ (June 2017). "Chlorhexidine and silver sulfadiazine coating on central venous catheters is not sufficient for protection against catheter-related infection: Simulation-based laboratory research with clinical validation". The Journal of International Medical Research. 45 (3): 1042–1053. doi:10.1177/0300060517708944. PMC 5536400. PMID 28534703.
- Clinically-approved drugs against CNS diseases as potential therapeutic agents to target brain-eating amoebae, by Ayaz Anwar, Kavitha Rajendran, Ruqaiyyah Siddiqui, Muhammad Raza Shah, and Naveed Ahmed Khan; ACS Chemical Neuroscience, DOI: 10.1021/acschemneuro.8b00484; October 15, 2018 – at https://pubs.acs.org/doi/abs/10.1021/acschemneuro.8b00484
- Zennaro F, Oliveira Gomes JA, Casalino A, Lonardi M, Starc M, Paoletti P, Gobbo D, Giusto C, Not T, Lazzerini M (2013). "Digital radiology to improve the quality of care in countries with limited resources: a feasibility study from Angola". PLOS One. 8 (9): e73939. doi:10.1371/journal.pone.0073939. PMC 3783475. PMID 24086301.
- "Colloidal Silver" (Last Updated September 2014). National Center for Complementary and Integrative Health. Retrieved 9 October 2016.
- Rosenblatt A, Stamford TC, Niederman R (February 2009). "Silver diamine fluoride: a caries "silver-fluoride bullet"". Journal of Dental Research. 88 (2): 116–25. doi:10.1177/0022034508329406. PMID 19278981.
- Deery C (2009). "Silver lining for caries cloud?". Evidence-Based Dentistry. 10 (3): 68. doi:10.1038/sj.ebd.6400661. PMID 19820733.
- Lancaster T, Stead LF (September 2012). "Silver acetate for smoking cessation". The Cochrane Database of Systematic Reviews (9): CD000191. doi:10.1002/14651858.CD000191.pub2. PMID 22972041.
- Kokura S, Handa O, Takagi T, Ishikawa T, Naito Y, Yoshikawa T (August 2010). "Silver nanoparticles as a safe preservative for use in cosmetics". Nanomedicine. 6 (4): 570–4. doi:10.1016/j.nano.2009.12.002. PMID 20060498.
- Alexander JW (June 2009). "History of the medical use of silver". Surgical Infections. 10 (3): 289–92. doi:10.1089/sur.2008.9941. PMID 19566416.
- Fung MC, Bowen DL (2008). "Silver products for medical indications: risk-benefit assessment". Journal of Toxicology. Clinical Toxicology. 34 (1): 119–26. doi:10.3109/15563659609020246. PMID 8632503.
- Brandt D, Park B, Hoang M, Jacobe HT (August 2005). "Argyria secondary to ingestion of homemade silver solution". Journal of the American Academy of Dermatology. 53 (2 Suppl 1): S105–7. doi:10.1016/j.jaad.2004.09.026. PMID 16021155.
- Okan D, Woo K, Sibbald RG (June 2007). "So what if you are blue? Oral colloidal silver and argyria are out: safe dressings are in". Advances in Skin & Wound Care. 20 (6): 326–30. doi:10.1097/01.ASW.0000276415.91750.0f. PMID 17538258.
- Rhee DY, Chang SE, Lee MW, Choi JH, Moon KC, Koh JK (October 2008). "Treatment of argyria after colloidal silver ingestion using Q-switched 1,064-nm Nd:YAG laser". Dermatologic Surgery. 34 (10): 1427–30. doi:10.1111/j.1524-4725.2008.34302.x. PMID 18657163.
- Jacobs R (2006). "Argyria: my life story". Clinics in Dermatology. 24 (1): 66–9, discussion 69. doi:10.1016/j.clindermatol.2005.09.001. PMID 16427508.
- Geyer O, Rothkoff L, Lazar M (December 1989). "Clearing of corneal argyrosis by YAG laser". The British Journal of Ophthalmology. 73 (12): 1009–10. doi:10.1136/bjo.73.12.1009. PMC 1041957. PMID 2611183.
- "ToxFAQs™ for Silver" (Page last updated: March 26, 2014). Agency for Toxic Substances and Disease Registry. Retrieved October 9, 2016.
- Moran, Lee. (2013-09-25) Man who turned blue after taking silver for skin condition dies. Nydailynews.com. Retrieved on 2016-11-26.
- Drake PL, Pribitkin E, Weber W (July 2009). "Colloidal Silver Products" (PDF). U.S. Department of Health and Human Services. Archived from the original on 3 February 2012.
- Chopra I (April 2007). "The increasing use of silver-based products as antimicrobial agents: a useful development or a cause for concern?". The Journal of Antimicrobial Chemotherapy. 59 (4): 587–90. doi:10.1093/jac/dkm006. PMID 17307768.
- Subcommittee on Spacecraft Exposure Guidelines, Committee on Toxicology, National Research Council (2004). Spacecraft Water Exposure Guidelines for Selected Contaminants. 1. National Academies Press. p. 324. ISBN 978-0-309-09166-4.
- Lansdown AB (27 May 2010). Silver in Healthcare: Its Antimicrobial Efficacy and Safety in Use. Royal Society of Chemistry. ISBN 978-1-84973-006-8. Retrieved 20 January 2013.
- Solsona F, Mendez JP (2003). "Water Disinfection" (PDF). World Health Organization.
- Richmond C (2008-10-16). "Ron Rivera: Potter who developed a water filter that saved lives in the third world". The Guardian. Retrieved 2009-05-16.
- Corbett S (December 24, 2008). "Solution in a Pot". New York Times. Retrieved May 15, 2009.
- Committee on Creation of Science-based Industries in Developing Countries, Development, Security, and Cooperation, Policy and Global Affairs, National Research Council of the National Academies, Nigerian Academy of Science. (2007). Mobilizing Science-Based Enterprises for Energy, Water, and Medicines in Nigeria. Washington, D.C: National Academies Press. p. 39. ISBN 978-0-309-11118-8.
- "Kolloidalt silver" (Last updated Feb 17, 2016). Livsmedelsverket (Swedish Food Agency). Retrieved 9 October 2016.
- "Vad gäller om jag vill sälja kolloidalt silver som biocidprodukt?". Kemi (Swedish Chemicals Agency). Retrieved 9 October 2016.
- "Colloidal silver". Memorial Sloan-Kettering Cancer Center. May 16, 2011. Retrieved January 2, 2013.
- Wadhera A, Fung M (March 2005). "Systemic argyria associated with ingestion of colloidal silver". Dermatology Online Journal. 11 (1): 12. PMID 15748553.
- Fung MC, Weintraub M, Bowen DL (October 1995). "Colloidal silver proteins marketed as health supplements". JAMA. 274 (15): 1196–7. doi:10.1001/jama.274.15.1196. PMID 7563503.
- "Over-the-counter drug products containing colloidal silver ingredients or silver salts. Department of Health and Human Services (HHS), Public Health Service (PHS), Food and Drug Administration (FDA). Final rule" (PDF). Federal Register. 64 (158): 44653–8. August 1999. PMID 10558603.
- Newman M, Kolecki P (October 2001). "Argyria in the ED". The American Journal of Emergency Medicine. 19 (6): 525–6. doi:10.1053/ajem.2001.25773. PMID 11593479.
- "Colloidal Silver Not Approved". U.S. Food and Drug Administration. 2007-02-12. Retrieved 2008-09-22.
- "FDA Warning Letter" (PDF). U.S. Food and Drug Administration. 2001-03-13. Retrieved 2008-09-22.
- "FDA Warning Letter". U.S. Food and Drug Administration. 2011. Retrieved 2013-04-11.
- Gaslin MT, Rubin C, Pribitkin EA (April 2008). "Silver nasal sprays: misleading Internet marketing". Ear, Nose, & Throat Journal. 87 (4): 217–20. PMID 18478796.
- "Regulation of colloidal silver and related products". Australian Therapeutic Goods Administration. 2005-11-09. Retrieved 2008-09-22.
- FDA Consumer Advisory (October 6, 2009). Dietary Supplements Containing Silver May Cause Permanent Discoloration of Skin and Mucous Membranes (Argyria).
- McSweegan E. "Lyme Disease: Questionable Diagnosis and Treatment" (Revised on April 4, 2016.). Quackwatch. Retrieved October 9, 2016.
- "Twelve supplements you should avoid". Consumer Reports. September 2010. Retrieved January 31, 2013.
- Colker D (May 2, 2009). "Scam 'cures' for swine flu face crackdown". Los Angeles Times. Retrieved April 3, 2013.
- "Man is fined after selling "cancer cure" which he made at home". Chelmsford Weekly News. 15 September 2014. Retrieved 16 November 2014.
- Dai T, Huang YY, Sharma SK, Hashmi JT, Kurup DB, Hamblin MR (June 2010). "Topical antimicrobials for burn wound infections". Recent Patents on Anti-Infective Drug Discovery. 5 (2): 124–51. doi:10.2174/157489110791233522. PMC 2935806. PMID 20429870.
- Roe AL (January 1915). "Collosol argentum and its ophthalmic uses". British Medical Journal. 1 (2820): 104. doi:10.1136/bmj.1.2820.104. PMC 2301624. PMID 20767446.
- Gautier J, Allard-Vannier E, Hervé-Aubert K, Soucé M, Chourpa I (November 2013). "Design strategies of hybrid metallic nanoparticles for theragnostic applications". Nanotechnology. 24 (43): 432002. doi:10.1016/S0140-6736(01)66545-0. PMID 24107712.
- Searle AB (1920). "Chapter IX: Colloidal Remedies and Their Uses". The Use of Colloids in Health and Disease. Gerstein-University of Toronto : Toronto Collection: London Constable & Co.
- Cantlie J (1913). "Some recent observations on sprue". BMJ. 2 (2759): 1296–7. doi:10.1136/bmj.2.2759.1282.
- Borsuk DE, Gallant M, Richard D, Williams HB (2007). "Silver-coated nylon dressings for pediatric burn victims". The Canadian Journal of Plastic Surgery = Journal Canadien De Chirurgie Plastique. 15 (1): 29–31. PMC 2686041. PMID 19554127.
- Searle AB (1920). "Chapter VIII: Germicides and Disinfectants". The Use of Colloids in Health and Disease. Gerstein – University of Toronto : Toronto Collection: London Constable & Co.
- "Silver dressings--do they work?". Drug and Therapeutics Bulletin. 48 (4): 38–42. April 2010. doi:10.1136/dtb.2010.02.0014. PMID 20392779.
- Tolaymat TM, El Badawy AM, Genaidy A, Scheckel KG, Luxton TP, Suidan M (February 2010). "An evidence-based environmental perspective of manufactured silver nanoparticle in syntheses and applications: a systematic review and critical appraisal of peer-reviewed scientific papers". The Science of the Total Environment. 408 (5): 999–1006. doi:10.1016/j.scitotenv.2009.11.003. PMID 19945151.