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Euthyroid Sick Syndrome

Euthyroid Sick Syndrome is defined in the online Merck Manual. According to that definition, here is how Euthyroid Sick Syndrome and Wilson’s Temperature Syndrome compare:

Euthyroid Sick Syndrome Wilson’s Thyroid Syndrome
Probably due to decreased T4 to T3 conversion Yes Yes
Thyroid Blood Tests Always Abnormal Typically Normal
Low Thyroid Symptoms None Severe
Persists after non-thyroid stress or illness has passed No Yes
Treated No Yes, reversible

Other than having one thing in common, Euthyroid Sick Syndrome and Wilson’s Temperature Syndrome are almost complete opposites. Euthyroid Sick Syndrome is all about abnormal thyroid blood tests in patients without low thyroid symptoms. The condition is not considered to need treatment because there are no symptoms and the tests go back to normal when the stressful illness has passed. On the other hand, Wilson’s Temperature Syndrome causes severe low thyroid symptoms and is undiagnosable with thyroid blood tests. The symptoms can persist for years after a stressful illness and can worsen with subsequent stresses. Without treatment patients may suffer indefinitely. Wilsons Temperature Syndrome is reversible and often responds dramatically well to proper T3 therapy.

About the Author:

Denis Wilson, MD described Wilson 's Temperature Syndrome in 1988 after observing people with symptoms of low thyroid and low body temperature, yet who had normal blood tests. He found that by normalizing their temperatures with T3 (without T4) their symptoms often remained improved even after the treatment was discontinued. He was the first doctor to use sustained-release T3.


  1. carol scott April 25, 2013 at 7:22 am - Reply

    I have symptoms of overactive thyroid: heart fluttering,throat constriction,weight loss and inability to gain,loss of appetite,depression. Blood test showed antibodies to peroxidase(62) and thyroglobulin(20);totalT4:4.2. My daughter age 53 has Graves’ disease and my younger daughter age 46 has Hashimoto’s. I made an appointment with an endocrinologist for May 17. I’m afraid he will want to do a biopsy,surgery and radioactive therapy. My older daughter had her thyroid removed but still has symptoms. How can I pursue this without surgery of radioactive pill?

  2. Denise July 5, 2013 at 6:11 pm - Reply

    carol scott and Dr. Denis Wilson,
    I was diagnosed with hyperthyroid Graves disease 20 years ago. At that time I was walking 4-5 miles 5x per week and weighed 140 pounds. Little did I know at that time that flouride interferes with the iodine feeding my thyroid. I was drinking a lot of tap water which has flouride in it. I don’t know how the government lets the water company dispense a hazardous waste without prescription that interferes with iodine absorption. In my opinion, this is criminal. Supposedly there’s only two medicines to treat this and one caused a rash and the other didn’t work. Radioactive iodine was administered and my thyroid died. I went from having 5x the normal amount of thyroid hormone to hypothyroid in 2 months. Afterward, I was gaining weight at a rate of 5 pounds every three months. I am now 245 pounds and find myself with uncontrollable hypothroidism at 200mg levothyroxine with a TSH of 7.8.

    After researching on medical websites I found out that low iodine intake can cause hyperthyroid and hypothyroid. In my case, I believe the flouride interfered with my iodine consumption or I wasn’t eating enough to compensate. I’m now trying to take in extra iodine. I make a tea with hot water, honey, apple cider vinegar to aid in digestion and elimination of waste with the addition of 1 drop of Logol’s iodine at 5%. Asians eat 1000x the iodine that Americans eat and the RDA of iodine for us Americans is well below the Asians. I would adjust my iodine consumption before letting anyone fool with my thyroid…from experience.

    • Dr. Denis Wilson July 9, 2013 at 6:28 pm - Reply

      Good points. Sometimes people don’t convert T4 to T3 very well. Iodine is very important, but there are other factors as well, for example, selenium, stress, adrenals, and so on. Iodine is important in thyroid hormone production but not so much in T4 to T3 conversion. People with high TSH (above 4) and low temps on 200 mcg of T4 due very well when they are switched to T3.

  3. JED July 19, 2013 at 1:45 am - Reply

    Make sure you are absorbing the Iodine, not to mention the selenium, tyrosine etc.
    I was taking two drops of Lugols per day with no change in my absorption rate. My Holistic Doctor told me to increase the Lugols to 6 drops per day, but still no real change. Then I accidently spilt some on my arm, and I rubbed it in.
    It gave me the idea of absorbing it through my skin. I did the Lugol’s test of applying one drop just down from the inside elbow crease, and watch to see how long it took to disappear. By applying it to my skin, I have increased the time it takes to disappear from 20 mins to 9 hours. I believe that you need to get it up to about 12 hours before you have retained the ‘normal’ amount. Dr Wilson might wish to comment on that.
    I have found that my absorbtion rates are not very good, and I suggest that as you know that your’s aren’t, that you think about what you are taking by mouth, and what you are actually absorbing. I have found that powdered products are better than tablets, for instance, and B vit. under the tongue by spray are better than tablets.
    Hope that helps.

  4. junee July 25, 2013 at 12:03 am - Reply

    My TSH test was 55.07. Do I take more T3 Amour or wean down.

    • Dr. Denis Wilson August 2, 2013 at 6:36 pm - Reply

      Sorry, we can’t give medical advice.

  5. Becca July 26, 2013 at 12:20 pm - Reply

    I have been put on a sustained release T3 100mcg, 1 in the a.m. My latest labs made my Dr happy, but I still do not feel well. He told me i do not have Hashis, my adrenals are fine, the RT3 was cleared, no Candida overgrowth, initial urine test for iodine showed a high level…I feel as though i have, at different times hypo symptoms (fatigue especially, weakness, can’t workout out, bloating, foggy brain, blurred vision) and hyper (especially at night…breathlessness, all over body anxiety, feeling of head fullness “rush” as well as startle reflex to noise, cannot sleep)

    When I told him I’m still not well, he told me he “can’t give me more T3” (?!) as though I were a drug addict begging for heroin. I’m actually wondering if this type of T3 therapy is the problem? Also, is this much T3 long term a problem in other areas? (Bone etc?)

    Can I take my Temps and chart them while I am currently on this dose of T3? Would it help to investigate this further in this way? I don’t know how to proceed.

    • Dr. Denis Wilson August 2, 2013 at 6:35 pm - Reply

      Hi Becca. Yes, it’s fine and often helpful for you to track your temperatures during treatment. One of the most important factors for feeling well on T3 is to keep the T3 levels steady. Steadiness is everything. In an effort to keep the T3 levels as steady as possible we recommend sustained-release T3. However, sustained-release T3 is usually designed to last only 12 hours, so it is usually best to take the doses every 12 hours. Some patients take up to 90 mcg two times a day. When T3 levels get unsteady patients can get side effects like fluid retention, achiness, fatigue, palpitations, jitteriness and so on. You can read all about the protocol in this free online version of the Doctor’s Manual: Best regards, Dr. Wilson

  6. Barbara Hughes April 12, 2014 at 3:55 am - Reply

    Traditional temperature readings from Dr. Equipment shows temp from 95°F to 98°F. Feeling hot to the touch,nurse reads temp on neck back and it shoots up to 99°F through 102°F. Is this indicative of any of the conditions that you are familiar with? Highest Regards.

    • Dr. Denis Wilson April 16, 2014 at 9:48 am - Reply

      Hi Barbara,
      No, I’ve not heard of people having higher temperature on the skin than they do in their core. I may not be understanding correctly but that doesn’t sound possible. Is it an equipment error?

  7. PK June 18, 2014 at 9:21 am - Reply

    Hi Dr. Wilson, I am perplexed I have been on Throyid medicine for ten years as my weight has gone up gradually in addition I now have a fatty liver and according to the test results the binding agents on the iron aren’t working correctly? what can I do. I am going in for an upper and Lower GI and EGD next month.

    • Dr. Denis Wilson June 22, 2014 at 3:19 pm - Reply

      I’m not sure what your temperature is running. I feel a low temperature is an indication that the thyroid hormone treatment is not properly balanced. Your doctor can call 800 420 5801 to arrange a free consultation to discuss your case.

  8. shumaila November 16, 2014 at 8:35 pm - Reply

    my mother is diagnosed hnaving euthyroid sick syndrome.her total T3 is 110 and total T4 is 10.6 and TSH is 5.40.she is being treated by an ent specialist.but still she is not feeling well.what should we do??

  9. Ronda December 15, 2014 at 12:58 am - Reply

    years ago while searching for any explanations to numerous very odd symptoms and numerous new diagnosis all the time, I stumbled across “Wilson’s low temperature syndrome”. i felt it fit me to a tee, particularly how I may have developed it – numerous, very extreme, long term bouts of depression over more than 10 years. at that time none of my doctors had ever even herd of this so needless to say, it was dismissed completely by all of them. a couple weeks ago I had a complete thyroidectomy. I was telling a friend today about some of my research on that and happened to run into the term “Non-thyroidal Illness Syndrome”, also called Euthyroid Sick Syndrome or Low T3 syndrome. that in turn lead me to this page and back to Wilson’s. I haven’t done any recent research on Wilson’s yet but before I do I was wondering if now that I have no thyroid and am on a steady daily of dose of levothyroxine, would or could Wilson’s even be relevant to me anymore?

    • Dr. Denis Wilson December 15, 2014 at 4:56 am - Reply

      Yes, for sure, many post thyroidectomy patients on levothyroxine still have low temperatures due to Wilson’s Temperature Syndrome.

  10. Liana April 2, 2015 at 1:30 pm - Reply

    I have been taking my temp for the past ten days and my temp ranges from 95.5 to 97.4 degrees. I went to the doctor yesterday after my dentist was concerned about my blood pressure being high (I’m 24 so that was concerning).My doctor said that the temp being low was normal, but ran several tests to rule out causes of fatigue and other causes of high blood pressure ESR, TSH, metabolic, lipids and many others but they all came back normal or no acute findings. should I be concerned and ask for different tests?

    • Dr. Denis Wilson April 5, 2015 at 5:27 am - Reply

      I don’t know how concerned you should be but low temperatures can definitely explain fatigue, and sometimes high blood pressure, as well as many other symptoms. If your temperature seems to be lower after passing through stress that is suggestive of Wilson’s Temperature Syndrome. Normalizing a low temperature can correct a lot of symptoms. If you don’t have symptoms then you may not care about getting your temperature corrected.

  11. Angela Truitt April 16, 2015 at 10:54 am - Reply

    I’m so confused! My PCP ran routine labs with the addition of TSH and Free T4 because will had some insomnia, mild tremor, palpitations and fatigue. I also have trouble losing weight. The test showed that my TSH was low, T4 was high so he ordered a rT3 and a thyroid ultrasound. The rT3 showed mildly elevated at 35 and ultrasound was negative. He said I have what’s called Euthyroid syndrome and said the symptoms would go away on their own after my stress in my life is better. I attempted to do some research on it and only found Euthyroid sick syndrome. Is this the same thing? My symptoms have gotten slightly better but I cannot sleep!! I try so hard but I can’t! On a typical night, I sleep 4-5 hours where I used to sleep 7-8. Should I obtain a secon opinion? I feel I am fatigued my heart rate is better but sometimes it reaches 125 at rest. I am on no medication. Please help! I’m so tired!

    • Dr. Denis Wilson April 19, 2015 at 7:37 am - Reply

      Hi Angela :D
      When your PCP said “Euthyroid Syndrome” I’m sure he meant, “Euthyroid Sick Syndrome.” Blood tests and ultrasounds don’t measure body temperature. Low body temperatures can easily explain low thyroid symptoms no matter what your blood tests say. If your symptoms are due to a low body temperature then you can’t really expect them to go away until your temperature has been normalized. You can check this list for a doctor near you: Good luck!

  12. judy May 18, 2015 at 8:45 am - Reply

    dr. gonzales seems to think that this is my fault

  13. Vanessa L. June 25, 2015 at 11:45 am - Reply

    I have always had a low temperature. I am overweight and have a stressful life. I have a lot of inflammation especially with my gut. I have all the symptoms of a low thyroid. The only other weird thing is I am always really hot and cannot tolerate heat. I keept my thermostat on 70 in summer. I’ve seen several MD’s and cannot seemed to feel better. I am 58.

  14. Bonnie October 2, 2015 at 2:07 pm - Reply

    Thyroidectomy in 2009 for thyca. On Synthroid and small amt Cytomel. I am cold all the time—- I feel like a freak. Sometimes I want to wear winter coat in the summer; I just do not feel well. I have high blood pressure and am taking Diovan HCT 325/25 and Sular 17 mg. I cannot sleep most nights— if I get to bed by 12 am I am up by 5am. At Drs office, my temps run from 95 to 97.1. Due to the cancer, they want to keep my TSH very suppressed. I have gained more weight after being thin and healthy all my life. I am willing to try the Wilson Protocol, but have to understand what, if any, dangers there are for me. PS. For years I suffered with diarrhea…. Explosive and unpredictable— I lived on Imodium every day so I could go to work. Regular docs told me I had Crohn’s disease; inflammatory bowel syndrome, only offering biologics and powerful drugs which I refused to take. Not giving up, I found a doctor on Internet who was willing to see me. He took lots of blood tests and said to stay off gluten and dairy for a year and see how I do. He had me buy certain capsules and Inflammax powder. After two months I was normal again! I am Gluten Free for 2 years and have very little dairy ( now that I am in my second year and “am cured”. God bless the doctor’s that look beyond their prescription pads, and we patients that persevere! Bonnie

    • Dr. Denis Wilson October 5, 2015 at 10:10 am - Reply

      Hi Bonnie, Nothing about what you describe in your case suggests to me that you are at any more risk than anyone else regarding T3 therapy. T3 suppresses TSH more than T4 so that should satisfy your doctors. Low iodine can contribute to thyroid cancer and other problems. Low temps can contribute to high blood pressure, insomnia, irritable bowel syndrome. Sounds like you have a lot of room for potential improvement.

  15. Evelien December 19, 2015 at 12:27 am - Reply

    I kind of have all the symptoms and nobody knows what is wrong with me.. tried traditional medicine, all kinds of hollistic remedies and therapies but all got worse. I do have anemea but was wondering as I am not overweight if the cause could be WTS?

    • Dr. Denis Wilson December 20, 2015 at 3:37 pm - Reply

      Certainly Evelien, people with normal weight or that are underweight can still experience WTS.

  16. Rena Sumter April 15, 2016 at 10:29 am - Reply

    Well my body temperature has been normal but I still have several of the other symptoms. It has been causing quite a medical conflict in my life. I wish I could get some answers because no one likes to take a lot of medications towards things that you know is going on with your body at the same time you know it’s not going to cure your symptoms. These days doctors seem to want to write prescriptions rather than diagnose I don’t want to become a guinea pig I want to be diagnosed I have headaches sometimes they can get very severe I’ve had an MRI nothing has showed on the MRI to contribute now I’m starting to have fingertips tingling toe tingling I have weight gain. in fact this is the heaviest I’ve ever been in my life. I don’t feel like I can go on like this much longer I do feel as though I need to diagnose. Is there is someone out there that can give me some answers and some help it would be greatly appreciated.

    • Dr. Denis Wilson April 24, 2016 at 6:51 pm - Reply

      Hi Rena :)
      You might consider checking your temperature with another thermometer just to be sure. You might want to check it with a glass/liquid metal thermometer (like the one Geratherm sells)

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