Iodine-induced thyrotoxicosis in a woman with a... - Thyroid UK

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Iodine-induced thyrotoxicosis in a woman with a multinodular goiter taking levothyroxine

helvella profile image

Care is always appropriate when using iodine.

As I read it, it took the best part of a year to recover.

Arch Intern Med. 1985 Feb;145(2):355-6.

Iodine-induced thyrotoxicosis in a woman with a multinodular goiter taking levothyroxine.

Reith PE, Granner DK.


In a 63-year-old woman with a multinodular goiter who was receiving suppressive therapy with levothyroxine sodium, iodine-induced thyrotoxicosis developed after povidone-iodine was applied to the surface of a granulating hip wound. Signs and symptoms of apathetic thyrotoxicosis developed on two occasions, once within a week after exposure of the wound to povidone-iodine soaks and again following repeated Hubbard tank debridement with added povidone-iodine. Iodine-induced thyrotoxicosis was confirmed by markedly elevated serum thyroxine and serum and urine iodine levels. On eliminating the sources of exogenous iodine and inhibiting thyroxine biosynthesis with propylthiouracil, the process was gradually controlled. A year later the patient was taking no medication and was clinically and chemically euthyroid. Apparently, iodine-induced thyrotoxicosis can result from passive diffusion of iodine into autonomous thyroid tissue. Iodine-containing preparations given to patients with multinodular goiters may result in thyrotoxicosis even if thyrotropin is suppressed with exogenous thyroxine.



[PubMed - indexed for MEDLINE]

21 Replies
shaws profile image

Just goes to show what happens when you treat a wound with iodine when on levo.

helvella profile image
helvellaAdministrator in reply to shaws

I don't think that the taking of levothyroxine was important in itself - but the fact that the patient had a very low (i.e. suppressed) TSH because of it.

Therefore, the hyperthyroidism occurred despite TSH not driving the thryoid to produce thyroid hormone. It occurred because of the multinodular goitre which made thyroid hormone when the iodine levels were high.

I'm thinking of the trillions of surgeries coated with betadine while the patient is also taking levothyroxine. There must be more to this.

Astridnova profile image
Astridnova in reply to Heloise

Oh, I didn't realise until I looked it up that Betadine contained iodine.

I wonder if this could also be a useful method of assisting iodine uptake.

Heloise profile image
Heloise in reply to Astridnova

Although conventional doctors may scoff at this but Betadine taken internally by drops (careful dosing) has successfully resolved cystic breast disease. The thyroid uses more iodide if I recall. Iodoral is often used to improve deficiencies.

If you want to find Dr. Berg on you tube. I think it was a TED talk where he discusses uptake of iodine through the skin. While it was discounted because of evaporation, he feels if you keep it wet (avoid evaporation) it is quite plausible. He is the only one that I've known to do that.

helvella profile image
helvellaAdministrator in reply to Heloise

I have zero problem with the idea that iodine and iodide can pass through the skin.

What I do discount is any meaningful result from the so-called iodine patch test. And evaporation of iodine is one reason to dismiss it.

I'd be extremely wary of taking betadine/povidone-iodine.

Heloise profile image
Heloise in reply to helvella

Well then I hope you don't have breast cysts:)

helvella profile image
helvellaAdministrator in reply to Heloise

Not sure which of my points you are referring to.

Skin absoprtion seems uncontroversial to me.

Patch test has been dismissed.

If it was the third one, then this abstract explains why I would be very wary - but I leave everyone else to make up their own minds.

Drug Chem Toxicol. 2014 Jul;37(3):268-75. doi: 10.3109/01480545.2013.846364. Epub 2013 Nov 12.

Povidone-iodine-induced cell death in cultured human epithelial HeLa cells and rat oral mucosal tissue.

Sato S1, Miyake M, Hazama A, Omori K.

Author information


Although povidone-iodine (PVP-I) has been used as a gargle since 1956, its effectiveness and material safety have been remained controversial. The aim of this study was to investigate the toxicity of PVP-I to epithelial cells in a concentration range significantly lower than that used clinically. Study design was in vitro laboratory investigations and in vivo histological and immunologic analysis. We examined the effects of PVP-I at concentrations of 1 × 10(-2) to 1 × 10(3) μM and 1 × 10(-4) to 1 × 10 μM on HeLa cells as a model of epithelial cells and rat oral mucosa, respectively, after 1 or 2 days of exposure. Annexin V/FLUOS was used to distinguish live, apoptotic and necrotic cells. The terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) method was also used to observe whether apoptotic epithelial cells exist in rat oral mucosa after 1 day of exposure of PVP-I. HeLa cells developed concentration-dependent cytotoxicity, and epithelium of rat oral mucosa was thinned in a concentration-dependent manner. HeLa cell apoptosis increased after 1 × 10(0) μM of PVP-I exposure for 2 days. In the TUNEL method, many apoptotic epithelial cells were observed in the rat oral mucosa after 1 day of exposure to diluted 1 × 10(-2) μM of PVP-I, but minimal apoptotic epithelial cells were observed using 1 × 10(-3) μM of PVP-I. Our findings suggest that exposure to PVP-I, of which concentrations are even lower than those used clinically, causes toxicity in epithelial cells. This knowledge would help us better understand the risk of the use of PVP-I against mucosa.


Apoptosis; HeLa cells; fluorescent staining; necrosis; rat oral mucosa; toxicity



[PubMed - indexed for MEDLINE]

Heloise profile image
Heloise in reply to helvella

Lugols is not the same type as povidone but Lugols is the same as betadine, at least in the U.S.

.Crow's® Lugol's Solution 2% is equivalent to USP standards or higher. This solution delivers 94% distilled water, 4% potassium iodide and 2% iodine. ... Each VERTICAL drop is approximately 3.00- 3.125 mg's of iodine/potassium iodide (approximately 1.250 mg iodine, 1.875 mg potassium ...

helvella profile image
helvellaAdministrator in reply to Heloise

Not according to Betadine!

Purdue Products L.P.

One Stamford Forum

Stamford, CT 06901-3431

For the Home

BETADINE® Solution is the aqueous solution of povidone-iodine 10%. It is used as a first aid to kill germs and help prevent infection in minor cuts, scrapes and burns.

Click here to link to specific product information.

BETADINE® Skin Cleanser is a sudsing, microbicidal antiseptic which yields a rich, golden lather. Used for hand washing and for general skin degerming, Betadine® Skin Cleanser significantly reduces bacteria on the skin.

For external use only.

Do not use in the eyes, over large areas of the body, or if you are sensitive to iodine or other product ingredients.

Ask a doctor before use in case of deep or puncture wounds, animal bites, or serious burns.

Stop use and ask a doctor if the condition persists or gets worse or if you need to use this product for more than 1 week.

Keep out of reach of children. If swallowed, get medical help or contact a Poison Control Center right away.

Please read full product label before use.

Heloise profile image
Heloise in reply to helvella

OK but only take Lugols if you develop breast cysts of any kind:)

Heloise profile image
Heloise in reply to Astridnova

I bookmarked these articles if you haven't already read them.

helvella profile image
helvellaAdministrator in reply to Heloise

It was the multinodular goitre - see my response to shaws.

Iodine should always be balanced with selenium but human bodies need iodine for many functions including making thyroid hormones and prevention of breast, ovarian and prostate cancers.

greygoose profile image
greygoose in reply to katwoo2

But they only need a certain amount. Too much is as bad as too little - as this poor lady has found out.

Heloise profile image
Heloise in reply to greygoose

Hi gg, I wonder about that balance. After reading about the urine test for iodine, it seems the amount you flush out, whether a little or a lot, seems to determine your need. It is a heavier halide and therefore pushes out the other two. So if you are bromide toxic or chlorine toxic, they will give up the receptor to iodine??? Wouldn't that mean that you will not overdose on iodine since that will also be expelled if you don't need it? What I need to know is how the thyroid iodine receptors are involved. I hated chemistry class, can you tell?

Here are the atomic weights of the four halogens:

fluorine 18.99

chlorine 35.45

bromine 79.90

iodine 126.70

greygoose profile image
greygoose in reply to Heloise

Ooooo! You're asking the wrong person there!

However, I have to say, I very much mistrust this theory of excess iodine being flushed out. I insisted on having an iodine test, because my doctor wanted me to take it (!). They only do a serum blood test here, but my level was so high it was amazing!

My gland wasn't doing very much at that time, so the recycled iodine from the NDT I was taking, wasn't being used to make hormone. And, as far as I can see, it was just sitting around in the blood. I wasn't taking any iodine suppléments at all, just the NDT. So, I think yeah, right, when people talk about iodine being flushed out and peed away.

helvella profile image
helvellaAdministrator in reply to Heloise

I don't understand what is meant by some of this.

1) Many posts here talk about the need, at least sometimes, for extra salt - meaning primarily sodium chloride. And how some take vast quanitities of it.

2) Your response suggests that we can be chlorine toxic. I don't see how that sits with 1).

3) Maybe I am equating chlorine with chloride? - but in your post you wrote about "bromide" and "chlorine" - either interchangeably between the atom and the ion - or not explaining sufficiently for me to grasp.

4) I am not convinced that atomic weight is the sole arbiter of whether xxx can replace yyy or zzz.

5) I think the poor woman in the original post suffered extremly from excess of iodine. If NOTHING else, it convinces me that exposure to significant amounts of iodine can cause severe issues. If someone had i) realised the patient had a multinodular goitre; ii) understood the possible impact of iodine on someone with such an autonomous multinodular goitre; iii) put i) and ii) together in a sensible way, she would not have suffered. She certainly couldn't get rid of excess iodine.

Heloise profile image
Heloise in reply to helvella

Rod, I am probably not using the right terminology, the important fact is that we get too much of the toxins that displace minerals we need. One of the articles brings out that heavy metals are affecting enzymes which I now think are the basic problem in creating disease. Even supplementing for deficiencies may not be the answer. Getting appropriate enzymes MAY be the answer. Just my opinion of course.

A brilliant board I followed for years by a medical doctor had this in the archives.

Sodium chloride (common

table salt); all of the other beneficial elements have been removed. The need is for unrefined, unprocessed real salt. Major producing companies dry their salt in huge kilns with temperatures reaching 1200 degrees F, changing he salt's chemical structure, which in turn adversely affects the human body.

Avoid the common refined table salt.

the ideal "salt" for humans is mineral salt which includes about 50 trace minerals besides NaCl. Of course, when these workers ( I assume anyone who sweats) lose "salt" with sweating then are also losing the trace minerals at the same time. Eventually, the pure NaCl will not be enough to avoid the other, as yet not recognized, trace minerals necessary for long term health.

Whether you consider the minerally unbalanced condition of the salt we use, the anticaking agents that prevent salt from doing some of its most important jobs in the body, or the chemicals and sugar that are added to it, table salt should be avoided because it is, without a doubt, hazardous to human health.

Excerpts from Ann Louise Gittleman

Can the reverse happen?

I had to cleanse my pin site wounds with iodine after a road accident. I used quite a bit of the substance 3 times a day for 4 months. 4 years after using it, I developed a goitre and wondered if there was a link.

My aunt took an iodine compound for her asthma for about 30 years, and became so exhausted at one point when she turned 70 she could not function. They finally figured out that the iodine had completely destroyed her thyroid. No doctor ever told her this could happen. Really terrible how she suffered. She is now doing well on her Synthroid at the age of 80.

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