Low T3 Syndrome I: It's Not about the Thyroid! | Chris Kresser
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Low T3 Syndrome I: It’s Not about the Thyroid!

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Fatigue—like this man is experiencing—could indicate low T3 disorder.
If you’re experiencing symptoms of a thyroid disorder—such as fatigue—it could be low T3 syndrome. iStock.com/OcusFocus

This article is part of a special report on Thyroid Disorders. To see a comprehensive eBook on thyroid health, click here.

Hypothyroidism involves high levels of thyroid stimulating hormone (TSH) and low levels of the thyroid hormones T4 and T3.

However, in my clinical practice I frequently see people with low levels of T3 with normal T4 and either low or normal TSH. This condition has been reported on in the medical literature for years but it is rarely acknowledged or discussed in conventional medical settings. (1) Most doctors (even endocrinologists) do not seem to know what causes it, or what to do about it. (I know this because I always ask my patients with this syndrome what their doctors said about it, and my patients’ response is almost always some variation of “not much”).

This particular pattern goes by three different names in the medical literature: Euthyroid Sick Syndrome (ESS), Non-thyroidal Illness Syndrome (NTIS), and Low T3 Syndrome.

NTIS has become the term of choice in the literature. However, I’m going to use Low T3 Syndrome in these articles because it’s more descriptive and accessible to the layperson.

What’s most important to understand about this condition is that, although it does involve low levels of T3 (the most active form of thyroid hormone), it is not caused by a problem with the thyroid gland. This is a crucial distinction and it’s what distinguishes Low T3 Syndrome from “garden-variety” hypothyroidism.

In this series we’re going to discuss:

  1. What causes Low T3 Syndrome
  2. Its clinical significance
  3. If it should be treated, and if so, how

But first we need to lay the foundation with a little basic thyroid physiology.

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Basic Thyroid Physiology

In order to understand Low T3 Syndrome, you’ll need a basic understanding of thyroid physiology. Regulation of thyroid metabolism can be broken down into the following five steps:

  1. The hypothalamus (a pea-sized gland in the brain) monitors the levels of thyroid hormone in the body and produces thyrotropin releasing hormone (TRH).
  2. TRH acts on the anterior pituitary (directly below the hypothalamus, but outside of the blood-brain barrier) to produce thyrotropin, a.k.a. thyroid stimulating hormone (TSH).
  3. TSH acts on the thyroid gland, which produces thyroxine (T4) and triiodothyronine (T3), the primary circulating thyroid hormones. The thyroid produces T4 in significantly greater quantities (in a ratio of 17:1) than T3, which is approximately 5x more biologically active than T4. (2)
  4. T4 is converted into the more active T3 by the deiodinase system (D1, D2, D3) in multiple tissues and organs, but especially in the liver, gut, skeletal muscle, brain and the thyroid gland itself. D3 converts T3 into an inactive form of thyroid hormone in the liver.
  5. Transport proteins produced by the liverthyroid binding globulin (TBG), transthretin and albumincarry T4 and T3 to the tissues, where they are cleaved from their protein-carriers to become free T4 and free T3 and bind to thyroid hormone receptors (THRs) and exert their metabolic effect.

Mechanisms of Low T3 Syndrome

As you can see, the production, distribution and activation of thyroid hormone is complex and involves several other organs and tissues other than the thyroid gland itself.

Hypothyroidism is a defect in step #3, because it typically involves a dysfunction of the thyroid gland itselfmost often caused by autoimmune disease (Hashimoto’s, Ord’s, Graves’) and/or iodine deficiency.

However, in Low T3 Syndrome, the problem generally occurs in steps #1, #2, #4 and #5. None of those steps are directly related to the function of the thyroid gland itself.

More specifically, Low T3 Syndrome can include the following mechanisms: (3)

  • Modifications to the hypothalamic-pituitary axis
  • Altered binding of thyroid hormone to carrier proteins
  • Modified entry of thyroid hormone into tissue
  • Changes in thyroid hormone metabolism due to modified expression of the deiodinases
  • Changes in thyroid hormone receptor (THR) expression or function

Low T3 Syndrome in Acute and Chronic Illness

Most of the studies on Low T3 Syndrome have been done on people suffering from acute, life-threatening illness. In the intensive care unit, the prevalence of abnormal thyroid function tests is remarkably high. More than 70 percent of patients show low T3 and around 50 percent have low T4. (4)

Many of these studies have indicated a direct relationship between Low T3 Syndrome the severity and both short- and long-term outcome of disease. (5) The lower the T3 level in critically ill patients, the worse the outcome tends to be.

However, studies examining thyroid hormone replacement in these situations have shown mixed results. In most cases—with the exception of cardiovascular disease—taking thyroid hormone did not improve outcomes. (6) We’ll discuss this in more detail later.

Recently, more attention has been given to Low T3 Syndrome in non-critical, chronic illness. Specifically, the question on everyone’s mind (including mine) is whether thyroid hormone replacement is useful in this situation, or if—as some have suggested—it could even be harmful.

In emotional, psychological or physiological stress, the body will convert excess T4 to reverse T3 (rT3) as a means of conserving energy for healing and repair. It is at least possible, therefore, that replacing thyroid hormone in these cases may not be beneficial.

On the other hand, in those suffering from long-term chronic illness, Low T3 Syndrome may be more reflective of pathology than adaptation, and this group may benefit from T4 or T3 supplementation.

We’ll explore all of these questions in more detail in the articles to follow, and I’ll also share some of my observations from my clinical practice. Stay tuned!

Articles in this series:

Research Spotlight: Health Coaching and Thyroid Health

Practicing Yoga Can Help Women Suffering from Hypothyroidism

Hypothyroidism is on the rise, affecting women disproportionately. One of the hallmarks of hypothyroidism is elevated TSH levels, and the disease is also often associated with poor lipid profiles and HPA axis dysregulation. Over time, hypothyroidism can contribute to coronary artery disease, obesity, and depression. To manage the disease, thyroid hormone medication is often prescribed, but long-term use can decrease bone mass and increase the risk of fractures.

Previous studies have shown that yoga can improve lipid profiles, diabetes, depression, anxiety, and more. A study from The Journal of Complementary and Integrative Medicine indicates that yoga may reduce the need for thyroid medications and therefore lead to better health outcomes.

Study Summary

The main objectives and findings of the article were the following:

  • In this pilot study, the researchers aimed to see if a long-term yoga program could improve TSH levels and lipid profiles.
  • 22 women, aged 30 to 40, with hypothyroidism completed a six-month yoga practice. Each session lasted one hour, and sessions were held four times per week.
  • At the end of the study, the participants had significantly reduced total cholesterol, LDL cholesterol, and triglycerides, and increased HDL cholesterol levels. Although TSH levels were not significantly different from baseline, they trended downwards, and seven of the 22 women were able to reduce their hormone medication dosage.

Key Findings and Significance

Excessive exercise can aggravate hypothyroidism symptoms, and many shy away from physical activity for fear of adverse outcomes. The findings of this study indicate that a slow movement exercise is beneficial for managing stress, improving metabolic profiles, and relieving some symptoms in women with hypothyroidism. Yoga incorporates exercise, awareness, and controlled breathing, indicating that even a meditation or breathing practice may have a place in hypothyroidism management.

Reference: Effect of 6 months intense yoga practice on lipid profile, thyroxine medication and serum TSH level in women suffering from hypothyroidism: A pilot study.

Health coaches support people who are trying to make big changes—like adopting a new diet or incorporating yoga into their exercise routine. How do they do it? By developing and honing skills like facilitating change and learning to listen. Find out more about becoming a health coach with the ADAPT Health Coach Training Program.

427 Comments

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  1. Hi, I used to have Cushing’s disease and had to have the entire pituitary removed in 2003. I am on all pituitary replacements and produce no TSH now. My T3 is 2.7, and Free T4 is 1.10…this month. I cannot seem to loose all the weight nor gain all my muscle back after Cushings. I want to try Armour instead of Synthroid but doctor will not prescribe. Am I producing enough T3?? For several years prior to this year I produced hardly any T3. Not sure but I was low on Vit. D, and have been told to supplement, and now have it at 38. Any advise would be helpful.

    • Im pretty similar
      Tsh 1.6 t3 2.8

      I had low vit d …got it up to normal and hasn’t made a difference i cant lose the weight either. I’ve tried everything and so frustrated too 🙁

      The weird thing is my t3 was 3.1 and lowered after put in trearment armour

  2. My daughter is 18 and was diagnosed with PCOS and insulin resistant at 16 and asked to reduce weight ASAP. We tried everything from high protein diet to 1200 cal diet but were not successful in droppint even 1 pound. Then we came across a natural diet which guaranteed weight loss even for PCOS patients. It was totally natural no medications just diet restrictions. We saw no harm in doing it just willpower as it was very strict. She lost 40 pounds on that diet in 3 months and then was on transition. Her T3 was fine before the diet. But since then she has been feeling Very Cold, hands turn blue and very weak. At first we thought it was because she lost so much weight but now her T3 was tested and was low. TSH and T4 are in normal range. T3 is going more down but endocronologist did all the testing and as all glands are normal they are refusing to treat her T3. She is alwasys tired, depressed, cold, brain fog, cannot concentrate in college etc. Natropathy suggested Cytomel or Armor Thyroid but nobody is willing to prescribe Armor Thyroid and with Cytomel 5 mg her heart beats go up. The endo suggested to stop Cytomel as it will be harmful BUT he has no solution for her low T3 and her other symtoms. What is your suggestion and since her T3 most probably got messed up because of the diet which was in August 2010 two years ago. How do we correct that problem.

  3. Well, always learning something new. We now have a bed that drops the head well below the feet. A $6000 monster.

    • That is a brilliant monster! The hospitals where I go have only a short little bed, or a recliner which doesn’t help enough. The shortie bed is ok because it makes me raise my legs which actually helps. I think that’s why I’ve also not fainted (so far) at the dentist – the bed tilts the head down below the legs.

    • yeah, and the weird thing was the outpatients department where the Blood Test Centre is sited paid for it, not the lab…Don’t know how we got that lucky!

  4. Hi Christine

    Good luck with your tinkering of the thyroid meds. As a phlebotomist, I just want to reassure you that if you lie down flat, you shouldn’t faint when you have your blood drawn. All the best.

  5. On Synthroid only, my tsh is 1.5, ft4 1.8 (lab range 0.7-2.5), and ft3 2.5 (lab range 2.5-6.5). I feel good enough relative to the misery before treatment, but only if I live like 70, taking it easy. If I try to exercise, I have days of rough recovery, feel hypo again. I used to be very fit and ran, now I can only stroll. I want to exercise again – could the addition of a little Cytomel help? If so, do I adjust my Synthroid down at all? If I drop down or go up by even a little, I don’t sleep well and get the “fuzzy” feeling.

    Another question – I faint from needles, so I’ve been using blood spot mail-in lab. The numbers have correlated well to how I felt finding my way to the best Synthroid dose. Are these results valid and reliable, and do they correlate well to venous draw?

  6. I have a low RT3 ratio 3.2. I have a doc who knows the right labs to draw and kindly agreed to prescribe ERFA Thyroid even tho he hadn’t known of it, at my suggestion. However, 2 wks on the med I started having fairly severe chest pain, so I stopped it. I had 2 office visits, $120 ea to get the ERFA Rx and now doc will only talk to me if I pay another $120, which seems exploitive to me. I asked stopthethyroidmadness folks who said I had to have an iron test and a saliva test for accurate cortisol level, correct these levels and then start an NDT. Otherwise I’d always have a reaction to NDT. I need help and support in order to navigate these hoops. Can you recommend a doc in my area Morgantown WV 26501 -1-1/2 hrs from Pittsburgh, PA who really understands this issue?

    My worse symptoms are depression/hopelessness, brain fog and dryyy skin. I was diagnosed with a goiter, tho fairly normal TSH in ’95, Synthroid 5 yrs, Naturethroid 5 yrs (great), reformated westhroid and naturethroid didn’t work, severe hair loss. Quickly became hyper on Armour…no med for last year, TSH 3.8 and have depression and progressive brain fog.

    • Did u get an answer about a dr to go to for thyroid in morgantown or Pittsburgh area?? I have been looking also.

      • I would love to know of a doctor in the Morgantown, WV area as well. Or if you could share the name of the doctor that is willing to prescribe Nature Throid or Armour as I’ve not had success in finding one who is willing to do so. Thanks!!

    • The Stop the thyroid madness people know their stuff and have helped a lot of people. You should spend some time on their website and educate yourself well. Sadly there are not enough doctors or endo’s who are educated to help you. Dr. Kessler is the exception, this site is very good.

  7. Any advice would be greatly appreciated. I am a 41 year old female with hypothyrodism. I curently take 75mcg levothyroxine, TSH level is 3.28. However, my T3 level is 28. I continue to have symptoms of hypothrodism. My doctor says that everything is ok because my TSH is within range, however, I am tried of freezing all the time and tring to lose weight with no success.

    • That’s one of the lowest T3 levels I’ve ever even heard of. Definitely not okay or normal. I would seek out a second opinion.

  8. I WAS DIAGNOSED WITH UNDERACTIVE THYROID AT THE AGE OF 26 – NOT TREATED
    HAD MY SON AT 28, DAUGHTER AT 31 WITH BOTH PREGNANCIES PUT AROUND 5 STONES IN WEIGHT – LOST THE WEIGHT AFTER BOTH BIRTHS WITH STRICT DIET AND EXERCISE .

    AT THE AGE OF 33 HAD SPINAL OP.(REMOVAL OF2 DISCS) SINCE THEN SEVERE OSTEOARTHRITIS -SCIATICA FALLEN ARCHES TORN LIGAMENT IN THE HEEL.

    AT 37 DIAGNOSED WITH M.E , SLEEP APNOA ( SLEEP WITH OXYGEN) AND PCOS MIGRAINE ALLERGIC RHINITIS PUT LOTS OF WEIGHT ON AND NO AMOUNT OF DIET OR EXERCISE CAN SHIFT IT. AT 40 HAD COMPLICATED HYSTERECTOMY WITH BLOOD TRANSFUSION.

    ALWAYS COLD- LOW MORNING TEMP.BETWEEN 35.9 AND 36.9 DEG. NOW I THINK I HAVE ALMOST EVERY SYMPTOM OF UNDERACTIVE THYROID BUT I’VE BEEN TOLD THE BLOOD TESTS ARE NORMAL

    FEMALE 61 Y OLD

    SERUM FREE TRIIODOTHYRONINE LEVEL (XAERQ ) 3.6 PMO/ L ( 3.5 – 6.5)

    SERUM FREE T4 LEVEL (XAERR) 15.2 PMOL/L (10.3 -23.2 )
    SERUM TSH LEVEL (XAELV) 3.25 MLU/ L (0.4 – 5.5 )

    LIVER FUNCTION TEST FASTING

    SERUM TOTAL BILIRUBIN LEVEL BELOW RANGE 4 UMOL/L (5.0 – 21.0 ) BELOW LOW REF
    SERUM ALKALINE PHOSPHATASE LEVEL 45 IU/L (30.0 – 120.0)
    AST SERUM LEVEL 15 IU/L (0.0 – 30.0)
    SERUM ALANINE AMINOTRANSFERASE LEVEL 16 IU/L (0.0 – 34.0)
    SERUM GAMA-GLUTAMYL TRANSFERASE LEVEL 87 IU/L (0.0 – 37.0)ABOVE RANGE HIGH
    SERUM TOTAL PROTEIN LEVEL 71 G/L (66.0 – 83.0)
    SERUM ALBUMIN LEVEL 44 G/L (35.0 – 52.0)
    SERUM GLOBULIN LEVEL 27 G/L (22.0 -42.0)

    SERUM LIPID LEVELS

    SERUM TOTAL CHOLESTEROL LEVEL 6.91 MMOL/L (0.0 – 5.19) -ABOVE RANGE
    SERUM TRIGLYCERIDE LEVELS 2.90 MMOL/L (0.0 – 2.23) -ABOVE RANGE
    SERUM HDL CHOLESTEROL LEVEL 1.06 MMOL/L (>= 0.9 )
    CALCULATED LDL CHOLESTEROL LEVEL 4.53 MMOL/L (0.0-3.35)-ABOVE RANGE
    SERUM CHOLESTEROL /HDL RATIO 6.5 (0.0 – 4.3) ABOVE RANGE

  9. Dear Dr.Kresser,

    I would very much apprceciate if you would look in to the symptoms /blood test results in my email and give me your opinion of what I should do.Thank you so much.
    Kathy
    I WAS DIAGNOSED WITH UNDERACTIVE THYROID AT THE AGE OF 26 – NOT TREATED
    HAD MY SON AT 28, DAUGHTER AT 31 WITH BOTH PREGNANCIES PUT AROUND 5 STONES IN WEIGHT – LOST THE WEIGHT AFTER BOTH BIRTHS WITH STRICT DIET AND EXERCISE .

    AT THE AGE OF 33 HAD SPINAL OP.(REMOVAL OF2 DISCS) SINCE THEN SEVERE OSTEOARTHRITIS -SCIATICA FALLEN ARCHES TORN LIGAMENT IN THE HEEL.

    AT 37 DIAGNOSED WITH M.E , SLEEP APNOA ( SLEEP WITH OXYGEN) AND PCOS MIGRAINE ALLERGIC RHINITIS PUT LOTS OF WEIGHT ON AND NO AMOUNT OF DIET OR EXERCISE CAN SHIFT IT. AT 40 HAD COMPLICATED HYSTERECTOMY WITH BLOOD TRANSFUSION.

    ALWAYS COLD- LOW MORNING TEMP.BETWEEN 35.9 AND 36.9 DEG. NOW I THINK I HAVE ALMOST EVERY SYMPTOM OF UNDERACTIVE THYROID BUT I’VE BEEN TOLD THE BLOOD TESTS ARE NORMAL

    FEMALE 61 Y OLD

    5.3mmol/L (2.5-6.1) PLASMA GLUCOSE,FASTING;-
    IMPAIRED FASTING GLYCAEMIA: 6.1 – 6.9
    DIABETES MELLITUS : >7.0
    PLASMA GLUCOSE, 2HOURS POST GLUCOSE LOAD: –
    IMPAIRED GLUCOSE TOLERANCE: 7.8 – 11.0
    DIABETES MELLITUS: >11.1

    THYROID ANTIBODIES
    THYROGLOBULIN AUTOANTIBODIES (XA1D4) < 20 IU/ML (0.0 – 20.0)
    THYROID PEROXIDASE ANTIBODY LEVEL (XADVU) = 0.9 )
    CALCULATED LDL CHOLESTEROL LEVEL 4.53 MMOL/L (0.0-3.35)-ABOVE RANGE
    SERUM CHOLESTEROL /HDL RATIO 6.5 (0.0 – 4.3) ABOVE RANGE

  10. Chris,

    Could you please clarify what do you consider normal for TSH, Free T3, Free T4
    I think my Free T3 is low (3.7) but it’s within the lab range…(2.8-7.1 pmol/L)
    Thank you!

  11. hi, i was hoping for a reply to my post, why my free T3 is 183 ref. range 210 to 440 and all the rest are within range. thank you. taking small dose of cytomel but it gives me strange side affects. ANY advice or reason free t3 is so low?

  12. Hi Doc!
    I am suffering from Vitiligo, I was told that one auto-immune disease puts you at the risk of developing other auto-immune diseases so I got my Thyroid profile done and it came out as :
    T3,Total 0.60 ng/ml (Reference Range 0.60-1.81)
    T4,Total 8.20 ug/dl (Reference Range 5.01-12.45)
    TSH 3.99 uIU/ml (Reference Range 0.35-5.50)
    Do I need to worry? Looking forward to your advice. Thanks!

    • A TSH of 4 indicates thyroid hypofunction, and you’re at the bottom of the range for T3. My guess is you’re having trouble converting T4 to T3; I covered the possible reasons for that in this article and elsewhere.

      • Thanks for getting back to me,Sir!
        I’m really worried. If you could please suggest me what should I do next.
        Thanks!

  13. i was diagnosed hypothyroid based ‘only’ on high tsh back in 07 when menopuase hit, only symptoms then were severe hot flashes but i was put on synthroid and i took it until about a year ago when i started feeling sick and i had hair changes, skin, muscle loss, eyebrows, you name it, i was a ‘fit’ 57 yr. old but felt like i was dying slowly. i decided to quit taking the med. and some things felt better but symptoms remained so went and had new labs and all numbers are within range except free t3 and i’m hoping some one here can help me? free t3 is183 ref. 210-440. dr. tried me on armour, i had a bad reaction so synthroid and cytomel, bad reaction, and then, just cytomel, i can’t take it so????? i don’t know what to do now. thanks.

  14. I am a 42 yo female who had a complete thyroidectomy (hasimoto’s thyroiditis) in 2003. Had a total hysterectomy in 2009. Wow, my life/health have never been the same. I have read, researched, experimented with everything I can find and pay for.

    Question: I have tried compounded slow release T3, cytomel, along with Armour. I do not seem to tolerate cytomel well (nervousness, heart palpitations, etc.) even in very small doses (2.5mcg) yet cannot really tell a difference with compounded SR T3 (even at 12.5mcg). I am currently experimenting with adjusting my Armour dose between 2 – 3 grains along with following Dr. Wilson’s Adrenal Fatigue protocol. I am also on BHRT. It is convoluted to be attacking all aspects of this hormonal trinity but nothing seems to be working and I can’t tell what is creating the symptoms.

    Ok, question: my TSH is still super suppressed, my free T3 is low, my free T4 is low. My FSH is high, my estrogen, progesterone, testosterone is low! Not sure what to do. Recently added some Tyrosine and Phenylalanine and Glutamine for energy and to decrease depression.

    Any suggestion? Should I even look at my TSH since I don’t have a thyroid gland. should I keep increasing my Armour dose to increase T3 and T4? Yet why do I have hyper like symptoms when I do? Adrenal Fatigue creating that? What about female hormones as they interplay into the whole hormonal orchestra. Help!

    • Hello Jennifer and Chris:

      Here are a few resources that I have found helpful; I am about to begin a protocol with LDN. Each of these resources may lead to more questions as well as some answers, such as the role of adrenals, in stabilizing on synthetic hormones, bio-identical hormones, or NDT. I have Hashimoto’s. I am currently on a T3 replacement only as years of Synthyroid at 200 mcg as well as Armour never alleviated the disabling symptoms of autoimmune disease.

      http://www.hormonerestoration.com/index.html

      http://www.stopthethyroidmadness.com/adrenal-info/

      http://recoveringwitht3.com/

    • Jennifer Im here because Im trying to learn more about t3 ( I had thyroid cancer so now have no thyroid. 200mcg synthroid and I feel depressed, tired, weak..36y.o. male)
      I was having constant anxiety/depression/brain fog and I asked my Dr to test my testosterone. He said it was in the “normal” range. So I took it to a hormone specialist and he laughed and said “ya its normal if you were in your 70’s”
      I went on testosterone injections and in two weeks everything changed.
      Im telling you this because he even prescribed my wife testosterone cream and I couldnt believe the change in her.
      She went from being tired, no energy, no sex drive etc to being happy, energetic, fat loss, always wanting sex lol…..
      I havent been on trt for a few years now because I couldnt afford it anymore and Im back to having no energy, memory problems, brain fog, lack of focus, no sex drive….
      You might want to look into it, but you need to find a hormone replacement clinic as your normal DR most likely wont prescribe a woman testosterone

    • you should read the books from Stop the Thyroid madness to gather some important information for your symptoms and what to treat first. The sttm website is also a very good source of info online and a way to get help fast!

    • I wonder if some of you have hypopituitarism. You would have hypothyroid symptoms and your labs show very low TSH and low free T3. This bloodwork would be done when your not on thyroid meds. I was diagnosed 9 years ago. They say it’s rare but I think most docs just don’t consider it or maybe have never seen a patient so don’t consider it or maybe dont know how to diagnosis it. Therefore people go for long periods of time trying to find answers.

  15. Hi Doc,
    I’m a 30 year old female that has been On synthroid for seven years. This past July I got extremely tired for weeks straight and saw my endo . My tsh on .112 was .8 and my t3 was 71. she increased my synthroid from .112mg to .125mg. In sept I got my levels checked again and my tsh was 1.5 and t3 was 76. Tidies the opposite of what we expected to happen, but I was feeling better and had more energy. In dec I got sick and my pcp thought I had bronchitis, I got a dose of steroids and antibiotics. I felt better after a few weeks, however since then my anxiety levels have been worse than ever. I have had several panic attacks and went to my psychiatrist. Although I have been on zoloft for 10+ yers she recommended I increase it to 125mg QD. For the last two months I have been taking 125mg zoloft and .125mg of synthroid. My panic and anxiety is still frequent. Have you ever seen or heard of anyone’s TSH levels going up by increasing synthroid? Or seen any patients T3 levels go down with increased synthroid? Do you think I should get another opinion?
    Also, I started taking singular in dec. Do you think that may effect my anxiety levels?

    • Katie,
      I would! I’ve been dealing with all of this since I got Mono a few years ago. You can read my story on my website. Keep in my site isn’t fully developed yet.

  16. Hello, Doc

    I have been on Tirosint for almost 9 months… raising the dosage from 25 to 75mcg as my levels had wavered and I kept hitting the wall of fatigue! I am at that point again with my TSH and T4 at good levels but T3 very low now. I exercise intensely every other day (lifting, boxing, boot camp) and walk/cycle/jog all alternate days. I eat really healthily…perhaps not enough calories actually…and have one hellova time just losing a few pounds! My Doc wants to add another med to help raise the T3 and I am not game. Any thoughts about how to help the T3 go up, how to boost my energy, and how my exercise and eating can actually result in weight loss? Thanks for any insight in advance!!

    • Just some ideas from my recent reading. If your TSH and T4 are at good levels, and the T3 is low, then why not just take a T4/T3 supplement? If that works, then you were having difficulty making T3. It is also possible your body could be reverse T3 dominant or for some other reason have problems making the T3. Have you had total and free T4/T3 tests? A thyroid microsomal antibody test? Tirosint seems to be just T4. I have heard that high stress (high cortisol – perhaps overtraining?) can inhibit T4 conversion to T3.

  17. Is it safe to take iodine supplements of 12.5 mg with synthroid to raise free T3? I was thinking I may have iodine deficiency and ordered it. Then, my lab tests came back showing TSH and T4 normal, but the free T 3 lower which prompted my dr to increase my synthroid dosage.
    your article is very well written.looking forward to next follow up.
    Oh and I realized that I,too, was on a low carb diet before I took the lab tests. Makes you wonder about the metabolism effects.

  18. I began researching Low T3 syndrome after coming home from the doctor today. My blood work results were received by my doctor and we met to review the findings. My TSH and T4 numbers all fell within the normal range. However, my T3 came back 0.00. I am a healthy 30-year old woman, somewhat overweight, but I do not have any known chronic disease. I’m interested to see the changes I experience once I begin treatment for this condition.

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