Discover more from DrV’s Newsletter, Notes, Essays, Articles, Videos, and Book Chapters
Povidone Iodine (topical 5,7.5,10%) against skin colonizations, dermal dysbiosis
POVIDONE IODINE is an impressively complex topic for something that most people think is cut, dried, and boring; the nuance and range of applications of POVIDONE IODINE are impressive
First version: 13Oct2011 Any updates [will be noted here at the top of the page]
Terms, Definitions, Concepts
Polyvinylpyrrolidone (PVP), polyvidone, povidone: this is a water-soluble binder that acts as a carrier for iodine; it was originally utilized intravenously as a plasma expander (thereby proving its safety)
Iodine: Iodine is a natural chemical element (stable halogen) with the symbol “I” and atomic number 53; iodine has broad-spectrum antimicrobial effects when applied topically or taken internally.
Iodide: Iodide ion is the ion I⁻; iodide has broad-spectrum antimicrobial effects when applied topically or taken internally.
Variations in concentration: Povidone Iodine products range in strength, with common concentrations being 0.5%, 5%, and 10%.
Variations in formulation: Beyond the base ingredient of Povidone Iodine, different companies use different detergents, solvents and other additives thereby explaining differences in sensitivity reactions and efficacy among different products.
Topical antimicrobial effect of POVIDONE IODINE
Pre~1965, the practice of medicine was based on “observable efficacy” and “common sense” whereas medicine in later years was much more based on “statistical efficacy” and “standard of care.” Clearly in the 1960s era, American society was fascinated by various modernization fantasies such as The Jetsons (1962-1963), Star Trek (1966-1969), Tang fake orange juice (1957/1959-), space travel (1968-), and an increasingly obvious anti-nature pro-synthetic stance encapsulated in the slogan, “better living through chemistry.” As such, “old medicine” was buried alive, and now one has to search older paper-based literature to find hidden gems of medical knowledge that were buried by the ever-growing avalanche of pharmaceutical propaganda and slavery to drug-funded “statistical significance” which nearly always translates to miniscule clinical benefit for real patients in the real world.
This 1958 article in the journal Archives of Dermatology published by the American Medical Association showed that 10% POVIDONE IODINE was a “fool-proof” treatment for skin infections and chronic colonizations, but most doctors these days have never heard of this cheap and safe treatment because it has been overshadowed by more expensive and dangerous/dramatic creams and lotions that fail to solve the problem and thus result in more return visits (profit for the doctors) and more prescriptions (profit for the drug industry).
“The self-serving willingness of the medical-pharmaceutical profession to consistently overlook the antimicrobial importance of iodine-iodide therapy is most likely tantamount to a crime against humanity as millions of patients are forced to suffer from lack of treatment and/or treatment with more dangerous, more expensive, and less effective antimicrobial drugs, which commonly have to be used in combination to achieve the same benefits provided by broad-spectrum low-cost high-safety iodine-iodide.” DrV
Long history of POVIDONE IODINE clinical/surgical use
POVIDONE IODINE is probably the most commonly used presurgical, surgical, and postsurgical wound disinfectant in the history of medicine. Busy surgeons commonly scrub with it several times per day for decades of their working careers, and patients are commonly swabbed and slathered with it before surgeries that last for hours. Therefore, the safety of POVIDONE IODINE is well-established for frequent use, use on broken skin, and extended (hours) of use on skin in a surgical setting. Typically the concentration in these surgical/skin applications is 10%.
Many of us have scrubbed our hands and forearms up to the elbows with POVIDONE IODINE as part of the presurgical scrub ritual, even repeating the procedure several times per day. However, these events —even when repeated daily—are of relatively short duration, don’t involve the entire body, and are done with a diluted concentration since water is applied along with the scrubbing solution.
Newer antimicrobial applications for POVIDONE IODINE in the mouth, eyes, nose
Beyond the external skin, we see increasing use of POVIDONE IODINE in the eyes against ocular infections (5% for 2 minutes), mouth—specifically the teeth—at 10% for 15 minutes, and nostrils/nares at 5% for 2-5 minutes.
Benefit of body-wide topical antimicrobial therapy; “diluted bleach baths” as topical antibacterial/antiseptic treatment of eczema (atopic dermatitis)
Body wash with topical antibacterial/antiseptic first became part of the medical treatment of eczema (atopic dermatitis) several years ago and is safe and effective as part of a comprehensive plan in the treatment of eczema (atopic dermatitis). The “body wash” in this case is actually a short-term soak in bathwater that has diluted bleach—weak enough to not cause harm but strong enough to kill the bacteria and other microbes; again see discussion in IM4.
Hype about “iodine allergy”
"Allergy to povidone-iodine seems not to be based on sensitization to iodine." Dermatol Clin 1990
I’ve seen several articles that have investigated so-called iodine allergy and have found it to not exist; people with reactions to iodine-containing drugs and foods appear to be having a reaction to something else because the more precise investigations (at least the ones that I have seen) have uniformly and unanimously concluded that the blame on iodine allergy is a misattribution.
If you have differing evidence, then please post it in the comments below or send me an email.
In summary thus far:
POVIDONE IODINE antimicrobial = safely used for frequent use (short periods of time)
POVIDONE IODINE antimicrobial = safely used for large-area use (short-moderate periods of time, including hours of surgical time) but on infrequent occasions
DILUTED BLEACH antimicrobial = safely used for full-body area use (short-moderate periods of time)
POVIDONE-IODINE is commercially available as 7.5% concentration marketed as BETADINE® Skin Cleanser
The following description (1-10) is from betadine.global
POVIDONE-IODINE (BETADINE®) Skin Cleanser has Triple-Kill Power versus clinically relevant pathogens.
It helps eliminate body odor causing bacteria
As a liquid antiseptic soap for general hygiene and for cleansing and disinfecting the skin.
Can be used as an effective infection control hand hygiene measure for skin cleansing and hand washing during viral infectious disease outbreaks such as hand, foot and mouth disease, impetigo, MRSA, flu (influenza, avian flu, swine flu), colds (rhinovirus, coronavirus) and Ebola.
Helps stop spread of infections in acne, pimple, minor cuts and wounds.
Helps remove offensive odor of the underarms, feet and body.
Helps prevent spread of fungal infections like tinea pedis (athlete’s foot or “alipunga”), tinea versicolor (ringworm or “an-an”), tinea cruris (jock itch or “hadhad”).
As a surgical scrub. Helps relieve skin itching
Contains 7.5% Povidone-Iodine
Available in 60ml, 120ml, 1 gallon
The fact that the company most famous in the world for selling POVIDONE IODINE is marketing this 7.5% solution as a “skin cleanser” for full-body use is obviously at testimony to their perception of safety and utility.
What I think is reasonable for small-scale application versus large-scale application
Risk factors for adverse outcomes with topical povidone iodine
I reasonably expect that this generally safe treatment could become more risky and problematic with 1) more covered area, 2) any open/active wounds or lesions, 3) higher concentration, 4) longer time duration, 5) application of heat—which I am reasonably expecting would promote systemic absorption, 6) systemic impairments such as dehydration, renal/kidney insufficiency, possible drugs that impair cardiovascular and renal function (eg, NSAIDs), extreme of age either very young or elderly.
Again, here are the major variables that modify risk of treatment:
open/active wounds or lesions,
longer time duration,
application of heat—which I am reasonably expecting would promote systemic absorption by increasing skin permeability and also by keeping the iodine in liquid solution,
systemic impairments such as dehydration,
drugs that impair cardiovascular and renal function (eg, NSAIDs),
extreme of age either very young or elderly
pre-existing problems, predispositions, and sometimes weird things happen and for whatever reason a person has an adverse effect to a treatment that we generally consider to be well tolerated.
Small-scale application to localized lesions: very safe
Small-scale application for example to isolated lesions such as local fungal infections like so-called “ringworm” appears to be safe with 10% POVIDONE IODINE as demonstrated in the article above from Archives of Dermatology published by the American Medical Association—YES, it was a small study of 50 patients but they demonstrated safety and 80% cure rate.
Larger-scale application for modest periods of time
For larger areas of skin and “outside the body” (eg, not vaginal), I think 5 to 10 minutes is plenty of time for 5-7.5%* POVIDONE IODINE provided that it's not causing important irritation, nothing that appears to be the so-called and largely disproved "allergy", and no systemic problems are manifest. *I mention 5-7.5% here instead of the more common 10% because I'm trying to be "on the safer side" and also because lower potency may actually be more effective.
I am also trying to be consistent with the formal recommendations for the product mentioned above: POVIDONE-IODINE commercially available as 7.5% concentration marketed as BETADINE® Skin Cleanser which they obviously describe as being used full-body: “underarms, feet and body”
I don’t think this has to be repeated daily for the treatment of dysbiosis/colonization; twice per week is likely sufficient (adapted from the success of the antimicrobial diluted bleach baths), along with other dietary and nutritional supplement interventions, necessary hormonal corrections (IM4, Chapter 4), and other antimicrobial treatments selected per patient and per laboratory/clinical findings. Cleaning of bedding, towels, clothes of course needs to be part of the plan.
Using it in the shower is generally easiest —apply with hand or washcloth, let it sit for a few moments, then rinse it down the drain.
Again: a few minutes should be enough and no need to use for longer than that; rinse it off and then dry off with a clean/uncontaminated towel and get into clean/uncontaminated clothes (day) or bedsheets (night).
Larger-scale application for long periods of time
If the skin lesions are severe and widespread, then we have more concern about systemic absorption if iodine is applied. I have looked for evidence/cases of harm from systemic absorption from topical/external skin application but have only seen a few cases among people with literally open wounds; I will work on reviewing these cases and will try to summarize in a future blog.
Better/newer research should have already been done
Except that the treatment is so inexpensive, some investigator working in a multimillion-dollar medical research school/institute should have already followed up on the clearly promising research and case reports that we already have but which need to be tested in a larger formal study to determine percentages and outlier problems. I don’t see any clinical studies using topical iodine on this, and specifically no follow-up on the should-have-won-a-Nobel-Prize-in-Medicine research of Patricia Noah that I have praised in Inflammation Mastery, 4th Ed and also mentioned in this recent post.
Disclaimer as usual: "This is not personal medical advice" but is something that I am still reviewing and will post more details when I have them.
If anyone finds good data related to this discussion, please share with me and I’ll review it and either include it if it is good or explain why I think it cannot be included.
DrV’s Newsletter, Notes, Essays, Articles, Videos, and Book Chapters is a reader-supported publication. To receive new posts and support my work, consider becoming a free or paid subscriber.