Colloidal Silver For Dogs: Is It Safe?

Colloidal Silver For Dogs
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Colloidal silver is incredibly popular with dog-owners. They view it as a cure-all for anything that’s wrong with their dog. Ask a question on social media about what to do with your dog’s ear infection, goopy eyes, diarrhea or cut paw. And 9 times out of 10, the answer will be “colloidal silver.”

But is it really the magic potion people think it is? And is it really completely safe for your dog? If you believe what you read online, it is. But many articles that make this claim are by companies that sell colloidal silver. Should you trust them?

Luckily, there’s been a lot of research. So after digging into many of the studies, here’s the real truth about colloidal silver …

What’s Colloidal Silver?

Silver has been used as an antibacterial agent for centuries. In the middle ages, people used silver utensils and goblets for their germicidal effects. Colloidal silver was first used in 1891 to sterilize wounds.

Silver use decreased after antibiotics were introduced in the 1940s. But silver is still used today in things like …

  • Wound dressings
  • Personal hygiene products
  • Cosmetics
  • Agricultural and industrial products

Scientists are getting interested in silver again because of antibiotic-resistant bacteria. Colloidal silver is becoming popular as an alternative antibacterial, antiviral and antifungal agent.

In chemistry, colloid means a liquid or gelatinous material with tiny particles throughout. Colloidal silver is a liquid suspension of minute particles of silver … usually in water. Suspended means the particles aren’t dissolved. The particles can be different sizes. But some are so small they’re nanoparticles.

Nano means 1 billionth. So a nanometer (nm) is one-billionth of a meter. It’s the scale that’s used to measure atoms and their molecules. A nanoparticle means it’s less than 100 nm. For comparison, a human hair is about 50,000 nm wide. So it’s too small to see.

When you buy colloidal silver, most labels show the silver content as parts per million (ppm). Or you may see it as milligrams per liter (mg/L). The number’s the same, so it doesn’t matter which term is used.

Types Of Colloidal Silver

Colloidal silver is a generic term used to describe several different products. You need to be careful to buy the right one. There are many impostors and poor quality silvers on the market.

True Colloidal Silver

This is the highest quality silver. True silver colloids don’t have any additives. They’re also the most expensive. True colloidal silver is excreted through urine and less of it gets stored in the body than other silvers.

Ionic Silver

Ionic silver contains silver ions dissolved in liquid … usually water. It’s often sold as colloidal silver and is a very popular product. It costs less but isn’t as effective as true colloidal silver. And it can bind with other elements in the cells and build up in the body. 

Hydrosol Silver

Hydrosol silver has a lower amount of silver atoms … around 96%. So it may not be as effective as colloidal silver. However, it usually has no protein additives or salts … and that’s a plus, because silvers with proteins and salts aren’t true colloidal silver …

Silver Protein

Silver protein products contain gelatin to suspend the silver particles. It’s not as effective as true colloidal silver … but beware, because it’s often sold as colloidal silver.

Silver Salt

Silver salt is used in conventional medicine. There are several types of silver salt … including silver nitrate, silver chloride and silver sulfate. They’re often used for antibacterial purposes in bandages and wound dressings. Silver salts are not colloidal silver. For example, silver nitrate is an inorganic compound that’s used as eye drops to prevent blindness in newborns. It would be toxic to take it orally, however.

Colloidal Silver Shouldn’t Be Silver

The color of colloidal silver gives you a clue about its quality. It’s always surprising to take some colloidal silver out of the bottle and find it’s brown! Brown doesn’t exactly make you think of silver!

But most colorless products sold as “colloidal silver” are likely ionic silver.

True colloidal silver needs an extra step in the manufacturing process. Adding a reducing agent (usually a sugar solution) and heating it turns it into colloidal silver. Then it will be yellow or brown colored … as true colloidal silver should be.

How Does Colloidal Silver Work?

A 2018 Australian study explained 3 known ways silver acts on microbes.

1. Silver particles can puncture the bacterial cell wall and disrupt cellular respiration (metabolic processes in the cells).

2. Silver ions can enter the bacterial cell. They inhibit cellular respiration and disturb metabolic pathways.

3. Once in the cell, silver can disrupt DNA and its replication.

Silver can also destroy biofilms. Bacteria produce biofilms that can form on skin and other surfaces in the body. They provide a protective layer for bacteria. Colloidal silver can remove this protection.

RELATED: Lower your dog’s exposure to heavy metals …

Does Colloidal Silver Work?

Colloidal silver is touted as a highly effective antimicrobial, antifungal and antiviral remedy. And some research shows it can …

  • Kill bacteria, including some antibiotic-resistant bacteria
  • Control some fungi and yeasts, including Candida and ringworm
  • Manage skin inflammation, infections and rashes
  • Heal burn and wound infections
  • Fight eye infections like conjunctivitis
  • Fight E coli and cholera bacteria
  • Manage sinus infections (as a nasal spray or rinse)

Some studies suggest it may help control viruses like HIV and Hepatitis C. And it may cause apoptosis (cell death) in certain cancer cells.

But there’s other research finding colloidal silver isn’t as powerful they claim. One study that tested 3 different colloidal silvers in vitro concluded …

“As the tested colloidal silver solutions did not show any antimicrobial effect in vitro on the microorganisms, claims of colloidal silver’s antimicrobial potency are misleading and there is no place for it as an antiseptic.”

Another study reported it was effective as an antimicrobial … but limited as an antifungal, and ineffective against viruses.

Is Colloidal Silver Safe For Dogs?

This is a big question and there’s some conflicting research.

Is Silver A Toxic Metal?

Heavy metals like mercury and lead are known contaminants that threaten public health … and your dog’s. So where is silver on the toxicity scale?

Silver (Ag) is a “transition metal” on the periodic table. Other transition metals include nutritional minerals like chromium, copper, zinc and iron. These other transition metals are considered essential nutrients.

But silver isn’t a nutrient. And it’s not technically a heavy metal. But silver can indeed be toxic.

Studies report cases of silver toxicity, such as eye irritation and allergic contact dermatitis. Silver may affect the liver, kidney, nervous system and blood. There’s also suspicion it can cause DNA damage or cancer.

And, even in the form of colloidal silver, it can carry some health risks. Read more detail about the safety of colloidal silver below.

Will Your Dog Turn Blue?

There are many well-publicized cautions about colloidal silver turning people’s skin blue. It’s a permanent condition called argyria from silver building up in the body. It’s usually happened to people who take it every day for long periods of time.

In fact, the risk of argyria is low … as long as you use true colloidal silver. Most cases of argyria come from ionic silver. And home-made “colloidal silver” is also to blame in many argyria cases.

So it’s unlikely your dog will turn blue from true colloidal silver. But there are some other side effects you should be concerned about. 

Does Colloidal Silver Harm Gut Bacteria?

You may (and should!) avoid using antibiotics … because you know they damage the bacteria in your dog’s microbiome.

Antibiotics don’t just kill bad bacteria … they kill friendly bacteria as well. And that’s a problem. Destroying good bacteria doesn’t just affect your dog’s digestive health … it also harms his ability to resist disease. That’s because 80% of your dog’s immune system is in his gut. So unbalanced gut bacteria leads to a weak immune system. And without a robust immune system, your dog can’t fight off bad bugs, viruses, parasites or even allergies.

RELATED: What you need to know about antibiotics …

So, knowing this, you might choose colloidal silver instead of antibiotics. But that can be risky too.

It’s controversial because people love colloidal silver so much … and there are contradictory studies. Most of the research has been done in rats and mice. It’s important to consider this risk to your dog though, considering the number of dogs with chronic health issues.

One 2015 University of Michigan in vitro study found that, even at high doses, colloidal silver didn’t affect the murine gut microbiome. (Murine means from the Murinae sub-family that includes many species of mice and rats.) Companies who sell colloidal silver often reference this study.

But several other researchers disagree.

In 2014 there was a study partly sponsored by FDA and Natlional Institute of Environmental Health Sciences. Researchers found colloidal silver (AgNP) caused a decrease in Firmicutes and Lactobacillus bacteria. They also analyzed the effects on genes. The analysis showed colloidal silver exposure lowered expression of important immunomodulatory genes.

The study concluded that oral use of colloidal silver does …

“ … indicate that the oral exposure to AgNP alters mucosa-associated microbiota and modulate the gut-associated immune response and the overall homeostasis of the intestinal tract.”

And in 2015, Belgian researchers stated …

“Our data indicate that oral exposure to Ag NP at doses relevant for human dietary intake can induce microbial alterations in the gut.”

These results are good reasons to avoid oral colloidal silver for your dog. But if you do decide to risk it, don’t ever use it for more than 2 weeks. And be sure to add pre- and probiotics to maintain the balance of your dog’s gut microbiome.

RELATED: The best probiotics for dogs …

Other Colloidal Silver Risks

It’s not just about turning blue, or gut health. There are other serious concerns when you give your dog internal colloidal silver.

Organ Damage

Research shows colloidal silver can stay in the organs for some time. The brain is especially affected. Studies show some worrying effects of oral dosing of silver nanoparticles (AgNPs) …

  • Silver was present in all examined organs, with the highest levels in the liver and spleen.
  • Silver cleared from most organs after 8 weeks … but not from the brain and testes.
  • AgNPs are toxic to mammalian cells in skin, liver, lung, brain, vascular system and reproductive organs.
  • AgNP given by inhalation, ingestion or intra-peritoneal injection was later found in blood … and caused toxicity in several organs including the brain.
  • AgNP caused developmental and structural malformations in non-mammalian organisms. 
  • Developmental exposure of mice to AgNPs disrupts the microbiome-gut-brain axis. Bacterial changes were linked to behavioral and metabolic alterations.
  • Developmental exposure of AgNPs results in long term gut dysbiosis, body fat increase and neurobehavioral alterations in offspring.

Developmental exposure to silver nanoparticles brings some serious health consequences. And that means you should never give colloidal silver to puppies.

Other reported side effects from long term use of colloidal silver include …

  • Muscle weakness
  • Kidney problems
  • Neurological damage, including seizures

It’s Suppressive Medicine

Holistic vets warn against using suppressive medicines to treat your dog. Suppressive medicines may relieve symptoms … but they drive disease deeper. And it often comes back … in a more dangerous form.

Because of colloidal silver’s antibacterial effects, it’s highly suppressive. That means it may not cure your dog. And it could cause a problem that’s worse than the one you started with.

In fact, veterinary homeopath Dr Dee Blanco says …

“The use of metals to suppress symptoms of illness has been around for more than 200 years. Metals were used to treat everything … from syphilis or burns to herpes, arthritis, and more. This practice of using metals, with their resulting toxicities, added a layer of disease on top of the disease being treated. 

“Modern day homeopaths understand that use of colloidal silver poses two dangers … and probably more. First, the suppression of the symptoms, driving the disease deeper. This isn’t a curative response. And secondly, blood and tissue toxicities when metals are not detoxified.

“Over-use of colloidal silver causes suppression and toxicity in the body. These must be treated in order to find a deep and permanent cure for the patient.”

Skin problems and ear infections are often a sign of something deeper in the body trying to get out. And if you treat them with “anti” medicines, you close off the exit. So it’s essential you avoid suppressive remedies like colloidal silver if your dog suffers from these problems.

The same applies to diarrhea. That’s the body trying to get rid of something toxic. So you don’t want to interfere with that process.

Bacterial Resistance

It’s ironic. Interest in colloidal silver has increased because of concerns about antibiotic-resistant bacteria. And studies do show it can be effective as a broad-spectrum antibiotic alternative.

But now many scientists worry about overuse of nanosilver. They fear it’s leading to bacterial resistance as well. 

Environmental Problems

Silver nanoparticles are used in many consumer products. It’s not just about colloidal silver supplements. They’re in textiles, medical products, domestic appliances, cosmetics, food containers and more.

And that means they end up polluting the environment. They’re especially toxic to aquatic life … because they harm microalgae that other species rely on for food.

There are also risks of soil contamination and damage to agriculture.

Drug Interactions

The Mayo Clinic warns that colloidal silver can interact with prescription medicines, including penicillin and antibiotics, as well as thyroid drugs. Don’t use colloidal silver if your dog is on these medications.

Official Warnings

In 1999, the FDA issued a warning about lack of scientific evidence supporting colloidal silver products. Despite all the research since then, they haven’t revised their statement.

The National Center for Complementary and Integrative Health also cautions that colloidal silver’s effectiveness and safety aren’t proven. The NCCIH is part of the NIH that studies usefulness and safety of complementary health approaches.

Should You Use Colloidal Silver?

Having reviewed the research, the risks of colloidal silver clearly outweigh the potential benefits. Despite some of the positive studies, it’s hard to find reasons to recommend using it. Especially because so many holistic veterinarians warn about problems it could cause your dog. And when there are so many safer remedies.

It’s an especially bad idea to give your dog colloidal silver internally. There’s a high risk of gut dysbiosis, organ damage and developmental problems. Maybe it’s slightly better than antibiotics … but it’s still not safe for your dog.

If you must use colloidal silver on your dog, stick to topical use.

But remember, your dog’s skin has a microbiome too. Any kind of antibacterial product will compromise your dog’s skin health. So you’ll still want to give him pre- and probiotics to help support his good bacteria. And never use colloidal silver longer than necessary.

RELATED: Natural topical antibiotics for dogs …

Alternatives To Colloidal Silver

Whenever you can, find a different way to treat your dog’s wounds and skin problems. Here are some ideas to help with typical problems. 

Skin Problems

Hotspots – You want to jump on hotspots quickly before they spread. clean the area and remove any crustiness and loose hair with plain soap and warm water. Dry thoroughly then apply a hotspot salve. Or follow the herbal protocol in this article.

Ringworm – Ringworm Is a fungal infection that shows as round hairless patches. You can dab it with undiluted organic, unfiltered apple cider vinegar several times a day. Or slice a clove of garlic In half and rub it on the area 3 times a day. 

Read this article for other home remedies for ringworm.

Allergies and Itchy Rashes – Make a paste by mixing colostrum powder with a little distilled water. Apply it to the area to soothe discomfort. You can wipe it off with a damp washcloth and reapply the paste 2 or 3 times a day.


If your dog has a cut or scrape, calendula is an excellent healing herb. It prevents infection, heals wounds, relieves pain and reduces inflammation. Buy calendula cream or lotion … or make your own from this recipe.

If you have nothing else around, even good old table sugar can help stop wound infections. You might want to tape or bandage the area so your dog doesn’t lick the sugar.

Ear Infections

Don’t disrupt your dog’s ear health by pouring colloidal silver or other antibacterials into it. Instead, if you need to wipe it, use organic witch hazel on a cotton pad. Green tea (cooled) can be soothing if your dog’s ear is inflamed and itchy.

One of the best herbal remedies for ears is mullein oil. HerbPharm makes a good mullein-garlic oil that works very well.

RELATED: Home remedies for ear infections …

Eye Irritations

If your dog’s eyes are red, read this post to find out what could be going on. If it’s not something serious that needs a vet visit, you can treat it at home.

Many eye irritations can be soothed with a simple salt water or chamomile tea rinse. And these homeopathic eye drops are great for different eye problems, including conjunctivitis.

Sore Paws

If your dog gets red or sore spots on his pads, use a healing salve to soothe them. Or you can make your own salt-chamomile foot soak recipe.


Always avoid using antibacterials of any kind for diarrhea. It may temporarily fix the runny poop … but it won’t solve the underlying problem.

There are plenty of natural ways to manage diarrhea. If your dog’s an adult, start by fasting him (give water only) for 12 to 24 hours. Sometimes fasting is all it takes to help the digestive system rest and renew.

Then give probiotics to help rebalance the gut bacteria. You can add slippery elm powder to soothe the gastrointestinal tract and help stop the diarrhea. Click on the link below for other home remedies for diarrhea.

RELATED: How to stop dog diarrhea …

Before closing, here are a couple more points about colloidal silver.

Don’t Make It Yourself

If you insist on using colloidal silver, don’t try to make it yourself … unless you’re a professional chemist. You’ll find plenty of instructions for making it online. Ignore them! You’d probably save money. But you’d also risk some serious side effects. 

Even properly prepared colloidal silver has risks for your dog. Don’t increase those risks with a home-made product.

Buying Colloidal Silver

If you want to buy colloidal silver, always buy a high quality, true colloidal silver. You’ll want a high ratio of positively charged silver – close to 100%.

Ask your holistic vet or another expert if you need help choosing. And don’t be fooled by high PPMs … they’re more toxic. A higher PPM isn’t better. A PPM of 10 is fine for most situations.

Don’t use silver gels, salts or protein products. And beware of ionic silver that’s marketed as colloidal silver. It’s not the same and won’t deliver the same results. And it has more risk of side effects and organ damage.

It might be tempting to keep that bottle of colloidal silver handy in your dog’s medicine cabinet. But don’t risk it! There are too many uncertainties … and plenty of safer alternatives.


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