Antivirals Effective Against Coronavirus?

[Wally]

@Hipsman - Highly recommend that you watch the webinar posted by @pamojja at Reply No, 119. Information is provided about using a nebulizer to dispense natural products like Vitamin C, hydrogen peroxide etc... Unfortunately. on my view of the webinar (from an iPad) there was no minute marker to be able to direct you to where he talks about this topic in his lecture. However, I think it was at least half way thru the 90 minute webinar. Long to watch, but I felt it was worth the extra time/effort to understand in more detail what natural treatments are being tried for treatment of Coronavirus -COVD-19, especially for lung complications. May not be what others think would be useful, but at least it gives you another point of view than what the CDC and the W.H.O. are currently recommending as possible immune support and/or symptom support for this highly infectious virus.

https://event.webinarjam.com/replay/20/v989va5i62u52sy6m7

You might also want to watch this video, which is a recent (Feb. 2020) lecture by Dr. Levy re using a nebulizer to deliver hydrogen peroxide. See hour/minute marker starting at 1:13:15

@Wayne

 

[Cipher]

Just found an of an interesting paper published Feb 2020 on disinfectants for coronavirus.

If you look at table 2 of the paper, you see that isopropyl alcohol (2-propanol) and ethanol are very effective.

But even more interesting is that povidone-iodine, even just a 0.23% solution, is a remarkably effective disinfectant for coronavirus. This is what surgeons use to disinfect their hands before an operation. Povidone-iodine has the advantage of being a persistent disinfectant: it continues protecting the skin hours after it is applied. Whereas alcohol quickly evaporates from the skin, so although it sterilizes, it does not offer any persistent protection from re-infection of the hands.

It might be an idea to make up a 0.23% hand sanitizer with povidone-iodine. You can buy 10% povidone-iodine online (that possibly 10% may be a bit too strong though for regular use, because quite a bit of the iodine is systemically absorbed). Then you could apply this 0.23% povidone-iodine hand sanitizer before you go out shopping etc, and it would help protect the hands from contamination. Also has the advantage of not drying out the skin like alcohol hand sanitizers.

What a great find, thanks @Hip! I think that 0.23% povidone-iodine might be a too low of a concentration to have a persistent effect because

• if we assume that 0.23% is the lowest effective concentration, then it won't last for hours as gradually is being inactivated
• 0.23 % might not stay 0.23 % when dried on skin, when it's mixed up with fats on the skin.

So while 0.23% povidone-iodine is a very effective acute disinfector for coronavirus, a higher concentration might be needed to ensure effect for several hours. I've tried to find research regarding at what rate povidone-iodine is inactivated on skin over time, but I haven't found any data on that. But maybe 1-3% might be better for persistent disinfection, but that's just a guess.

Another use-case for povidone-iodine is as a mouthwash:

In Vitro Bactericidal and Virucidal Efficacy of Povidone-Iodine Gargle/Mouthwash Against Respiratory and Oral Tract Pathogens.
RESULTS:

PVP-I gargle/mouthwash diluted 1:30 (equivalent to a concentration of 0.23% PVP-I) showed effective bactericidal activity against Klebsiella pneumoniae and Streptococcus pneumoniae and rapidly inactivated SARS-CoV, MERS-CoV, influenza virus A (H1N1) and rotavirus after 15 s of exposure.

CONCLUSION:
PVP-I 7% gargle/mouthwash showed rapid bactericidal activity and virucidal efficacy in vitro at a concentration of 0.23% PVP-I and may provide a protective oropharyngeal hygiene measure for individuals at high risk of exposure to oral and respiratory pathogens.

Evaluation of the bactericidal activity of povidone-iodine and commercially available gargle preparations.
RESULTS:
(1) PVP-I killed all the test strains after 30 s of exposure. (2) The mean reduction rate in bacterial count immediately after gargling was 99.4% for PVP-I, 59.7% for CHG and 97.0% for CPC. (3) Findings of the questionnaire study revealed that the PVP-I gargle was evaluated highest in terms of taste, feeling after gargling and odor among all the gargles tested. (4) At the middle school where the use of the PVP-I gargle was encouraged, the absence rate due to common cold and influenza was significantly lower as compared to those at middle schools where another gargle was used.


CONCLUSION:
Of the 3 gargles tested, PVP-I showed the highest bactericidal rate and the highest reduction rate in oral bacterial count. Encouragement of the use of the PVP-I gargle contributed to the decrease in absence rates due to common cold and influenza, indicating that encouragement of gargling with PVP-I is useful for the prevention of common cold and influenza.

Prevention of respiratory infections by povidone-iodine gargle.
.. Patients were asked to gargle more than 4 times/day with povidone-iodine gargle over extended periods of time, i.e. from several months up to over 2 years. The incidence of episodes of acute exacerbation of chronic respiratory infections decreased significantly when compared with that before use of povidone-iodine gargle. Episodes of infections with Pseudomonas aeruginosa, Staphylococcus aureus (including MRSA) and H. influenzae were reduced by about 50%. Results of this study suggest that povidone-iodine gargle is effective in providing a significant reduction in the incidence of acute exacerbations of chronic respiratory disease. We assume that the colonized bacteria were destroyed and thus infection could not occur. Therefore, povidone-iodine gargle may be used in these patients as a preventive therapy. ...

Abstract
This study is conducted to determine the different types of microorganisms found in the saliva of individuals with varying degrees of oral hygiene, also to determine the effectiveness of 1% Povidone Iodine (Betadine) 1% gargle oral antiseptic as a pre-procedural mouthrinse in individuals with varying degrees of oral hygiene, and lastly to be able to determine the duration of the effectiveness of the solution. The cheek mucosa of the patients are procured of saliva specimens without prior rinsing of 1% Povidone Iodine and the saliva sample obtained was placed on a test tube with thioglycollate culture media and was labelled. The patients are asked to rinse or to gargle immediately with 1% Povidone Iodine at full strength (20ml.) for about 30 seconds. After two hours, the cheek mucosa was then again swabbed and placed on the second test tube. After four hours, the same procedure was done and the saliva specimen obtained was labelled and placed on the third test tube. The result of this study revealed that 1% Povidone Iodine used as a pre-procedural mouthrinse has a bactericidal effect in the microorganism concentration resulting to the reduction of surviving microorganisms up to four hours which is the limitation of the study.

So rinsing one's mouth with povidone-iodine and gargling might reduce the risk of getting sick with the coronavirus, and it may also reduce the risk of superinfections with URTI-causing bacteria if you catch the coronavirus. Poviodine-iodine has a persistent effect on the mouth mucosa, just like on skin, for up to 4 hours (maybe longer, they didn't test). Povidone-iodine mouthwashes tend to be used at concentrations around 1%.

I've looked for research regarding the safety of povidone-iodine nasal spray, but I have to my surprise not found much on that, apart from this article;

Firebrick Pharma's mission was to create a nasal spray that would kill viruses using the same disinfectant agent as Betadine – povidone-iodine.
It took years of development to turn povidone-iodine into a safe nasal spray because the nose contains cells that are easily damaged. It has now been tested in more than 300 people across three clinical trials.

 

[Cipher]

Not to sound like an alarmist, but if shit hits the fan and the ICUs becomes full and the hospitals run out of ventilators, a bag valve mask might be good thing to have at home, just in case. They cost around 10-20$ each. Here's how to use it.

 

[Hip]

So while 0.23% povidone-iodine is a very effective acute disinfector for coronavirus, a higher concentration might be needed to ensure effect for several hours. I've tried to find research regarding at what rate povidone-iodine is inactivated on skin over time, but I haven't found any data on that. But maybe 1-3% might be better for persistent disinfection, but that's just a guess.

The povidone-iodine solution I made up for myself for hand sanitization, I used a 1% solution.

I guess you could also use regular 10% povidone-iodine solution if you wanted to.

With 10%, there would be quite a bit of systemic iodine absorption: I calculated that if you used 1 ml of a 10% povidone-iodine solution, then you would slowly absorb about 5000 mcg of iodine on each application. But that's not that much, as there are iodine supplements for sale which are 15,000 mcg per tablet.

However high intakes of iodine are contraindicated in Hashimoto's thyroid disease, and are not recommended for people taking ACE inhibitors and ARB blood pressure drugs. High iodine intake can also raise potassium levels.

So I reduced the 10% solution down to 1%, to reduce iodine absorption.



My understanding is that the iodine is slowly released from povidone-iodine solution, so it remains active for some time. This Google search says that for povidone-iodine solution 0.1% to 1%:

Residual activity lasts only 4–8 hours, therefore frequent reapplication of dressings is required.

So we might assume that povidone-iodine applied to the hands might provide protection for a good 4 hours, before reapplication is required.

I am not sure why povidone-iodine is not being recommended as a means to combat coronavirus, as it would seem better than alcohol, which only disinfects the hands when you apply it, but does not provide lasting protection like povidone-iodine.


Very interesting about the povidone-iodine gargle / mouthwash studies you quoted. When I first looked into the possibility of using a povidone-iodine gargle, I came across a study (that I can't find now) which said that povidone-iodine had no effect in reducing the incidence of common colds. So I assumed that gargling would not be helpful. But the studies you have quote above suggest that gargling with diluted povidone-iodine could help prevent catching viral infections.

My thought is that you could also apply povidone-iodine solution to your lips and the area around your nostrils, so that if you accidentally touch your mouth or nose, there would be a level of virucidal protection.



Another protective strategy might be taking the garlic extract called allicin: this paper found in a placebo controlled trial, the group given allicin had a lot fewer colds than the control group (24 colds for the allicin group versus 65 for the control group).

Coronavirus is one of the viruses that causes the common cold, so if allicin can reduce the risk of catching a cold, it may reduce the risk of catching the COVID-19 coronavirus as well.

Thus an allicin capsule daily might buy some protection against catching COVID-19.



The herb echinacea is another useful strategy, as studies have found that:

echinacea can reduce the risk of getting a common cold by more than half

Source: here.

I can vouch for echinacea: decades ago when I was still healthy (before I developed chronic fatigue syndrome from a viral infection), I would always carry some echinacea tablets with me to work. You know that feeling when you initially start to come down with a cold? I found that if I took echinacea at that crucial early stage, within the first 6 hours of that feeling coming on, it would invariably prevent the cold from manifesting. But once the cold gets a grip, echinacea I found did not help.

 

[Hip]

Some weeks ago already mixed up some 1% povidone-iodine solution, which I placed in a small spray bottle that I carry in my pocket, for disinfecting my hands if I go out in a public place.

I also wanted to give povidone-iodine spray bottles to my parents, who are in their 80s and thus the most vulnerable, but unfortunately they are both taking ramipril blood pressure drugs, which is an ACE inhibitor, and I came across some websites which said:

Concomitant use of iodine with potassium-containing products or ACE inhibitors may result in hyperkalemia.

Source: here

When used with ACE inhibitors and ARBs, iodine may result in an increased level of potassium in the body, which may be dangerous.

Source: here

 

[Wayne]

The author of the following 6-minute video uses iodine in his very effective sinus rinse. I've still not done this, but if I suspected I was exposed to the coronavirus, I'd probably do it pronto. -- I'm also keeping in mind doing hydrogen peroxide baths after going out if we start getting cases in our local area.

Chronic Sinus Problems? Try the Bulletproof Sinus Rinse

 

[splusholia]

Some weeks ago already mixed up some 1% povidone-iodine solution, which I placed in a small spray bottle that I carry in my pocket, for disinfecting my hands if I go out in a public place.

I also wanted to give povidone-iodine spray bottles to my parents, who are in their 80s and thus the most vulnerable, but unfortunately they are both taking Ramipril blood pressure drugs, which is an ACE inhibitor, and I came across some websites which said:

Source: here


Source: here

Sorry if this has already been mentioned, but could it be used as a mouthwash?

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5986684/

‘PVP-I gargle/mouthwash diluted 1:30 (equivalent to a concentration of 0.23% PVP-I) showed effective bactericidal activity against Klebsiella pneumoniae and Streptococcus pneumoniae and rapidly inactivated SARS-CoV, MERS-CoV, influenza virus A (H1N1) and rotavirus after 15 s of exposure.’

 

[Cipher]

I am not sure why povidone-iodine is not being recommended as a means to combat coronavirus, as it would seem better than alcohol, which only disinfects the hands when you apply it, but does not provide lasting protection like povidone-iodine.

It's so out of fashion that it's not even purchasable here in Sweden, I had to import it from Germany! I think it mostly comes down to the temporary discoloring of the skin that people don't like.

Some weeks ago already mixed up some 1% povidone-iodine solution, which I placed in a small spray bottle that I carry in my pocket, for disinfecting my hands if I go out in a public place.

I also wanted to give povidone-iodine spray bottles to my parents, who are in their 80s and thus the most vulnerable, but unfortunately they are both taking Ramipril blood pressure drugs, which is an ACE inhibitor, and I came across some websites which said:

Source: here


Source: here

I'm 99% sure that what those sites are referring to is the fact that oral administered iodine often comes in the form of potassium iodide, and that one should be careful with potassium sources as ACE inhibtors can increase the risk of hyperkalemia.

On drugs.com's interaction checker I put in different iodine sources (including povidon-iodine), but only potassium iodide was marked as an interaction with Ramipril, and that was in regards to the potassium salt. I've search on PubMed quite a bit, and I can't find anything regarding iodine itself increasing potassium levels.

Even potassium iodide shouldn't be a problem, as the potassium dose is miniscule compared to what a potato contains (>500mg elemental potassium):

Emergency 130 milligrams potassium iodide doses provide 100 mg iodide (the other 30 mg is the potassium in the compound)

Sorry if this has already been mentioned, but could it be used as a mouthwash?

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5986684/

‘PVP-I gargle/mouthwash diluted 1:30 (equivalent to a concentration of 0.23% PVP-I) showed effective bactericidal activity against Klebsiella pneumoniae and Streptococcus pneumoniae and rapidly inactivated SARS-CoV, MERS-CoV, influenza virus A (H1N1) and rotavirus after 15 s of exposure.’

Yes, check this post.

 

[IThinkImTurningJapanese]

Also has the advantage of not drying out the skin like alcohol hand sanitizers.

No, it's rough on hands as well.

 

[ellie84]

They are trialling tocilizumab, off-label, for patients with pneumonia and respiratory failure.

 

[Hip]

No, it's rough on hands as well.

Does povidone-iodine dry out the skin then, or cause some other skin issues? I've only used my 1% povidone-iodine solution a few times, and did not notice that much.

Possibly they might have been a bit drier the next day after application, but I am not sure.

 

[Cipher]

No, it's rough on hands as well.

Source? From what I've read povidone-iodine has a very good skin compatibility.

In vitro evaluation of skin sensitivity of povidone-iodine and other antiseptics using a three-dimensional human skin model.

Povidone-iodine (PVP-I) is an antiseptic which has been widely used in various fields. It was reported to have a weaker skin irritancy than other antiseptics in the Draize skin irritation test using rabbits. Recent increased concern for animal welfare requires us to use skin models in the tests as an alternative to animal testing. Actually, there are some skin models already commercialized, which are available to evaluate skin irritancy caused by e.g. chemical reagents, cosmetics or medicines. In this study, we evaluated the potential of a PVP-I solution and other antiseptics to cause irritation using a cultured human skin model (three-dimensional skin model) under conditions similar to clinical use. This skin model has two layers like a real skin, such as the dermis and epidermis which includes the cornified layer. For the evaluation of skin irritancy in this model, cell viability was evaluated by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay as an endpoint. Antiseptic formulations such as benzalkonium chloride (BAC), benzethonium chloride (BEC), chlorhexidine gluconate (CHG) and alkyldiaminoethylglycine hydrochloride (AEG) were used in this study. As a result, PVP-I showed a significantly weaker skin irritancy compared to the other antiseptics. The present in vitro study results revealed a correlation with the results of previously conducted in vivo skin irritancy tests using rabbits.

It's not clear in the abstract, but in the full-text they compared PVP-I (10%) to ethanol (80%), and the difference was big. Figure 1: 10 minutes contact time: Control 100% cell survival, PVP-I 99% and ethanol 50 %.

Now to be fair, ethanol-based hand sanitizers (containing emollients) generally have decent skin compatibility, much better than soap (R).

 

[Hip]

I'm 99% sure that what those sites are referring to is the fact that oral administered iodine often comes in the form of potassium iodide, and that one should be careful with potassium sources as ACE inhibtors can increase the risk of hyperkalemia.

On drugs.com's interaction checker I put in different iodine sources (including povidon-iodine), but only potassium iodide was marked as an interaction with Ramipril, and that was in regards to the potassium salt. I've search on PubMed quite a bit, and I can't find anything regarding iodine itself increasing potassium levels.

It's possible the drugs interaction checker does not mention interactions between topical povidone-iodine and ACE inhibitors like ramipril because it is assumed the povidone-iodine will only be used for short periods of a few days, during wound healing of cuts and grazes. But maybe long-term daily use of povidone-iodine on the reasonably large surface area of the hands is a different issue?

This paper says:

Povidone iodine in one study has been associated with increase in measured potassium up to 1 mmol/L, the mechanism of which is unknown.

Normal potassium level in the blood is 3.5 to 5 mmol/L. Moderate hyperkalemia starts at 6.1 mmol/L, and severe hyperkalemia starts at 7 mmol/L. Ref: 1

My mother is already diagnosed with high blood potassium, and has been advised to avoid high potassium foods. That's why I originally looked up whether there might be a connection between iodine supplementation and potassium, and to my surprise, found that there was some suggestion that iodine can increase blood potassium levels.

So at least for my mother, from what I can work out, long-term daily use of a povidone-iodine hand sanitizer might not be wise.

 

[Cipher]

It's possible the drugs interaction checker does not mention interactions between topical povidone-iodine and ACE inhibitors like ramipril because it is assumed the povidone-iodine will only be used for short periods of a few days, during would healing of cuts and grazes. But maybe long-term daily use of povidone-iodine on the reasonably large surface area of the hands is a different issue.

This paper says:


Normal potassium level in the blood is 3.5 to 5 mmol/L. Moderate hyperkalemia starts at 6.1 mmol/L, and severe hyperkalemia starts at 7 mmol/L. Ref: 1

My mother is already diagnosed with high blood potassium, and has been advised to avoid high potassium foods. That's why I originally looked up whether there might be a connection between iodine supplementation and potassium, and to my surprise, found that there was some suggestion that iodine can increase blood potassium levels.

So at least for my mother, from what I can work out, long-term daily use of a povidone-iodine hand sanitizer might not be wise.

The paper in question tested what happened if poviodon-iodine was applied on the skin puncture site when a plasma potassium analysis was to be made. So it's purely an analytic interaction from the povidon iodine that contaminated the test tube. I haven't found any indication that non-potassium containing iodine sources can increase potassium levels in the blood.

 

[Hip]

Here is the study I saw earlier which found gargling with iodine mouthwash did not prevent catching colds; but intriguingly, they found gargling with plain water several times a day reduced the amount of colds people caught by one-third. Though it was not a well-conducted study: it was not blinded; people knew which treatment they were getting. So perhaps we should not place too much reliance on its results.



This article about a University of Edinburgh study says gargling with salt reduces the duration of a cold by about 2 days, because the body uses salt to make antiviral bleach. The chloride ions in the salt are used by cells to make the bleach hypochlorous acid (HOCI), which fights viruses.

Whether salt gargling can also prevent catching a cold I am not sure.



If the body manufactures bleach for antiviral purposes, then I guess it might also be an idea to swish very diluted household bleach around the mouth, which perhaps might provide additional antiviral defense (though I've found no evidence for this online).

Very diluted household bleach (0.05% sodium hypochlorite) oral swishing is recommended by some dentists for oral hygiene purposes — see this article. So it is safe to regularly use as a mouthwash, if household bleach is diluted down 100-fold.

Household bleach bottles contain a 5% solution of sodium hypochlorite (NaClO).

In the article, they add half a teaspoon (2.5 ml) of regular household bleach in 4 oz (120 ml) of water, to make up the solution used for swishing around the mouth.


An alternative might be gargling 3% hydrogen peroxide, which is a common oral hygiene practice.

 

[Cipher]

Here is the study I saw earlier which found gargling with iodine mouthwash did not prevent catching colds; but intriguingly, they found gargling with plain water several times a day reduced the amount of colds people caught by one-third. Though it was not a well-conducted study: it was not blinded; people knew which treatment they were getting. So perhaps we should not place too much reliance on its results.

That study also used between 0,23% and 0,47% povidone-iodine, which is maybe a too low of a concentration to be effective.

This article about a University of Edinburgh study says gargling with salt reduces the duration of a cold by about 2 days, because the body uses salt to make antiviral bleach. The chloride ions in the salt are used by cells to make the bleach hypochlorous acid (HOCI), which fights viruses.

Whether salt gargling can also prevent catching a cold I am not sure.

Interesting! I found a study investigating both salt gargling and nasal irrigation for the common cold:

A pilot, open labelled, randomised controlled trial of hypertonic saline nasal irrigation and gargling for the common cold

Abstract

There are no antivirals to treat viral upper respiratory tract infection (URTI). Since numerous viruses cause URTI, antiviral therapy is impractical. As we have evidence of chloride-ion dependent innate antiviral response in epithelial cells, we conducted a pilot, non-blinded, randomised controlled trial of hypertonic saline nasal irrigation and gargling (HSNIG) vs standard care on healthy adults within 48 hours of URTI onset to assess recruitment (primary outcome). Acceptability, symptom duration and viral shedding were secondary outcomes. Participants maintained a symptom diary until well for two days or a maximum of 14 days and collected 5 sequential mid-turbinate swabs to measure viral shedding. The intervention arm prepared hypertonic saline and performed HSNIG. We recruited 68 participants (2.6 participants/week; November 2014-March 2015). A participant declined after randomisation. Another was on antibiotics and hence removed (Intervention:32, Control:34). Follow up data was available from 61 (Intervention:30, Control:31). 87% found HSNIG acceptable, 93% thought HSNIG made a difference to their symptoms. In the intervention arm, duration of illness was lower by 1.9 days (p = 0.01), over-the-counter medications (OTCM) use by 36% (p = 0.004), transmission within household contacts by 35% (p = 0.006) and viral shedding by ≥0.5 log10/day (p = 0.04). We hence need a larger trial to confirm our findings.

The people behind the study have a website here with some more information.

Another thing that might be a good idea is inhaling hypertonic saline using a nebulizer. I haven't found much on this with regards to pneumonia, apart from this paper.

 

[Cipher]

The situation in Italy is very severe, and other countries will soon follow suit:

https://www.reddit.com/r/Coronavirus/comments/fgky3y

https://www.reddit.com/r/Coronavirus/comments/fg7hsv

Makes projects like this very important:

https://www.reddit.com/r/Coronavirus/comments/fgz25e

 

[Hip]

That study also used between 0,23% and 0,47% povidone-iodine, which is maybe a too low of a concentration to be effective.

I can't figure out the concentration used in the studies you quoted.

In this paper you quoted on the povidone-iodine mouthwash test in a school, the mouthwash used was called Isodine, which this paper says is 7% povidone-iodine.

But the second paper says the Isodine manufacturer's instructions say to dilute with water 2 ml → 60 ml, equivalent to a concentration of 0.23% of the active ingredient.

So I am not clear on what concentration they used in the school study.

Interesting! I found a study investigating both salt gargling and nasal irrigation for the common cold:

I guess it's probably more effective to do both salt gargling and salt nasal irrigation.

Maybe just spraying salt solution into the nostrils using a nasal spray bottle might work just as well as nasal irrigation.

 

[Hip]

Not to sound like an alarmist, but if shit hits the fan and the ICUs becomes full and the hospitals run out of ventilators, a bag valve mask might be good thing to have at home, just in case. They cost around 10-20$ each. Here's how to use it.

Wouldn't critical-care patients with COVID-19 infection require mechanical ventilation continuously for days? If you had someone in the house with COVID-19, you would not be able to ventilate them 24/7 with a hand-operated ventilator.

 

[Mary]

I think it's worth investigating whether or not colloidal silver or silver nanoparticles may be effective against COVID-19. I had always thought colloidal silver was only effective against bacteria. I've used it successfully a couple of times for strep throat and on occasion for unknown pathogens making me sick. So I was surprised to come across a study showing antiviral properties of silver nanoparticles against HIV-1: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2818642/

Here's a study about the antiviral action of silver nanoparticles against bacteriophage ϕX174, murine norovirus, and adenovirus serotype: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3993170/

And here's an article about silver nanoparticles being used in an antimicrobial gel (I know, not antiviral): https://www.ncbi.nlm.nih.gov/pubmed/19473014

About all we generally hear from mainstream medicine re colloidal silver is the risk of argyria, discoloration of the skin caused by a buildup of silver in the body. However, I've read that a lot depends on the product being used - the size or type of silver particles, the concentration of particles, etc. and also I think you generally have to ingest a lot over a long period of time to develop this condition.

In any event, I've used colloidal silver products on several occasions and plan to keep some on hand!

eta: I know that not all viruses are alike and something that works against one virus won't work against another one. I just think this should be investigated at least.

I also know that televangelist Jim Bakker is being sued by the State of Missouri for touting a colloidal silver product as a cure for COVID-19. I have no great fondness for Jim Bakker, but can't help wondering if he was right!