In some individuals with a low tsh, only the t3 is elevated and the ft4 or fti is normal. P shares important new information about how hashimotos autoimmune thyroiditis can make you feel bad, even if your tsh, t4, t3 are normal. T4 does us no good if we cant get it into an active form t3. The decreased tsh level seen in sch results from the pituitarys response to minor elevations in serum or tissue t4 and t3 levels. Doctors give trusted answers on uses, effects, sideeffects, and cautions. Free t4 still has a story to tell and its not something you want to. Oct 02, 2019 low free t3 and free t4 levels may indicate low thyroid function, but they may also indicate a condition known as euthyroid sick syndrome or low t3 syndrome. However, many organisations agree that a reading of 2. As i mention to others when all else fails aim for a ft4 of roughly 1. Introduction screening and treatment of subclinical.
Subclinical hyperthyroidism sch is defined as a low thyroid stimulating hormone tsh level with normal free t4 and free t3 levels in patients without specific symptoms of hyperthyroidism. Aug 28, 2017 tsh fluctuates due to the change in the trh. Aug 16, 2007 the t4 and t3 hormones come directly from your thryoid. Patients can be severely hypothyroid with a high tsh and low ft4 or fti, but have a normal t3. The low t3 and t4 would normally stimulate the pituitary and hypothalamic glands to increase trhtsh production, however, they are unable to increase production. Subclinical hyperthyroidism sch is defined as a low thyroidstimulating hormone tsh level with normal free t4 and free t3 levels in. Free t4 tests can be inaccurate in some people who have interfering substances present.
This thyroid test analyzer will help you understand your tsh, t3, t4, and other thyroid function test results. Jul 12, 2017 tsh, free t4, and free t3 can all fall within the normal range, and yet if these antibodies are elevated, they indicate that you have an underlying autoimmune thyroid disease, along with the. This article is part of a special report on thyroid disorders. This means that a person is at risk of developing hypothyroidism but is not yet showing any noticeable symptoms. To manage decreased tbg, insulin sensitivity and blood sugar tests like fasting blood glucose, fasting insulin levels, glucose tolerance test, and hba1c are also helpful. High free t3 and low free t4 with normal tsh medhelp. If tsh is increased and both free t4 and free t3 total t3 are within normal ranges. In any given individual t4 and t3 concentrations remain relatively constant. Currently, i have two or three clinically hypothyroid patients, who have the aforementioned paradoxical normal tsh, low t4, and comfortably normal or high free t3. The goal is to get your t4 to better convert to t3. In hyperthyroidism, both t4 and t3 levels are usually elevated, but in a small subset of hyperthyroid patients only t3 is elevated t3 toxicosis. This is why a complete thyroid panel is often needed. A further tier of regulation of th action is provided at a prereceptor level by a family of. Rarely, patients may have problems with their pituitary or hypothalamus that render the tsh less useful as a test for thyroid function.
Low levels of t4 with high tsh indicates hypothyroidism. Hashimotos autoimmune thyroidpatients with normal tsh. Hmm usually the ldn has the opposite effect, of lowering the tsh. Oct 15, 2019 the authors begin by stating that subclinical hypothyroidism is characterized by normal t4, t3, free t4, and free t3 with an elevated tsh. It made be better but i was like 50 pounds heavier so it made me depressed and i hated myself. I assume you are taking no thyroid medications, supplements or herbs. Since t3 is the most active useable form of thyroid hormone that can be used in the cells of the body, free t3 is critically important. What causes a low tsh level with a normal free t4 level. And these patients have an increased risk of cholesterol abnormalities, heart disease, mental illness, and pregnancy complications even though their symptoms are relatively mild. Nov 27, 2008 you would take medicine because your tsh is high, and it is not ok for it to stay high. When t4 levels rise or fall, tsh will respond accordingly to correct the levels. It is important to first make sure that it is low t3 that is the culprit of your symptoms. Some people may have heard about thyroid stimulating hormone tsh levels, and how they work in your body. When there is underconversion of t4 to t3 we cant have normal thyroid responses.
Jul 10, 2018 high tsh, normal t4, normal t3 this is the pattern weve been discussing in this post and will usually present with hypothyroid symptoms. Amiodarone can or 6mthly tsh, t3, t4 estrogens can t4 by tbg androgens, corticosteroids can t4 tbg methadone can t3, t4 tsh pulsatile release, peaks during night takes 46wks for tsh to reflect circulating thyroid hormone levels abnormal tsh can persist for several months after achieving clinical euthryoid. Dec 15, 2017 instead, since you demonstrate cardiac issues at high levels of t4, leave that the ft4 as moderate, goal of roughly 1. If tsh and free t4 are normal or lower than the normal range, and the free t3 levels are lower than average. Blood tests for thyroid functiontsh, total t4, free t3, tsi, and othersare an important part of diagnosing and treating thyroid disorders. Normal ranges for adults generally fall between these values. T3 testing rarely is helpful in the hypothyroid patient, since it is the last test to become abnormal. T4 is converted in t3, so your total t3 is low bound t3, t3 is bound to thyroxine binding globulin tbg, prealbumin and albumin. If this is a total t3 that is high with normal free t4 and tsh, then it is likely high binding proteins usually due to estrogen, ie birth control pill, etc. High tsh and high free t4 what doctors want you to know. Im going to tell you why hashimotos negatively affects your quality of life even if your tsh and your hormone levels are normal.
But,as per sources normal tsh levels for the average adult range from 0. Thyroid function tests american thyroid association. My tsh and t4 levels are low, and my t3 levels are very high. It feels like the easy answer for optimal t3 levels. The reasons for t3 and t4 being within the normal reference range but having tsh lower than 0. Jul 16, 2018 for this reason, it would seem intuitive that if a low tsh is commensurate with good health, that a high free t3 and free t4 would be, as well. Normal thyroid labs with symptoms hypothyroidism low t3 syndrome. With a non functioning thyroid, you will expect to see the following. The prevalence of sch depends on the level of tsh used as a threshold. This can happen for two different reasons, which have classifications. There are many treatments and ways to raise your free t3 level. Most normal people have levels in the top 14 of the range.
Once the t4 in the bloodstream goes above a certain level, the pituitarys. High tsh, normal t4, low t3 this pattern may be an indication that you are having issues with thyroid conversion and most often presents with hypothyroid symptoms. Abnormal tft results guidance abnormal thyroid function tests. This condition is very similar to hypothyroidism, but some patients with it may not experience symptoms, whereas all patients with hypothyroidism will experience symptoms. The untreated patients with sch had significantly higher bone mineral density.
Thyroid function test interpretation tft interpretation. The journal american family physician says that levels of tsh over 4. Hi everyone, i am new to this forum and hope someone can give me some insight as to what is going on. Im googling everywhere my condition but still cant find an answer, im 23 and the way doctors reacted to your daughter condition was exactly the same for me except my t4 is high 29. The tsh should be in the range of lownormal to reflect healthy function in the body. The body produces more tsh to stimulate the thyroid when t3 and t4 levels are low. For this reason, it would seem intuitive that if a low tsh is commensurate with good health, that a high free t3 and free t4 would be, as well. The pituitary, hypothalamus and adrenals also called the hpa axis are all part of the endocrine system and communicate with one another throughout the day. Specifically, total t4 and t3 andor free t4 and t3 can be tested. Low tsh, low free t3 and low free t4 posted in lab results discussion boards. I will most likely pay out of pocket for an alternative, but wanted to run it by you guys.
Unfortunately, that is not adding a small cytomel to a very high ft4, but a revamp to much lower ft4 levels and pushing the ft3 with t3 or just switching to dtendt. A very common problem that we see in our office everyday is low t3 due to thyroid underconversion. I have been steady gaining weight and have no energy in the last year but my doctor says i am not hypothyroid. I cant give you a medical diagnosis or a prescription, but the problem may be that your body isnt converting the t4 in your medication to the t3 your body needs. It is now widely accepted that there are 6 major patterns of thyroid dysfunction and only 1 of these patterns responds well to thyroid replacement.
Unfortunately mainstream doctors often do not test free t3. Hi, i am a 25 yrs old male i have my thyroid t4 t3 rates in very normal stable rate. Im going to tell you why hashimotos negatively affects your quality of life even if your tsh and. Laboratories use reference ranges to compare blood test. I had half my thyroid removed 3 years ago due to a benign nodule. Abnormalities of thyroid hormone metabolism during. T3 and t4 are important hormones produced by the thyroid gland and both t3 and t4 is made up of a protein and iodine in the form of iodide. This sounds like graves disease hyperthyroidism or the very earliest phases of hashimotos thyroiditisplease consult an endocrinologist asap. Tsh, free t4, and free t3 can all fall within the normal range, and yet if these antibodies are elevated, they indicate that you have an underlying autoimmune thyroid disease, along with the. This occurs when the thyroid is underactive and does not produce enough t4. Tsh communicates to the thyroid gland to release the thyroid hormones. In normal health the brain and the pituitary are able to sense the amount of free t4 and free t3 circulating in the blood and adjust the amount of tsh produced by the pituitary so that levels of free t4 remain in the normal range in much the same way as a central heating thermostat turns on the heat when the temperature is too low and turns it. Understanding thyroid function tests and normal ranges.
Especially t3, because of the direct effect it has on thyroid hormone as opposed to t4, which is more of a carrier for t3. Would usually not treat this situation but recheck labs using different lab or. As thyroid hormone has a long half life, it takes 34 weeks for a new steady state level of thyroid hormone to equilibrate in. Most people tend to blow off their free t4 level because it isnt the free and active hormone, especially when compared to free t3. To determine if the levels of thyroid hormone have been corrected, a repeat set of blood tests, usually a tsh and perhaps a free t4 or free t3, should be obtained after about 4 weeks following initiation of treatment. I was diagnosed with graves disease in 2011 after an auto accident. Abnormal tft results guidance abnormal thyroid function. My t4 and t3 are also normal, but my tsh was high and the doctor put me on medication and it made me feel much better. In the case of tsh, the optimal zone is skewed far toward the low end of the standard lab low high range. Accordingly, a high clinical index of suspicion is required, and confirmation of. In response to this low level of thyroid hormones, the pituitary releases tsh to try and stimulate thyroid. In the cases of free t4 ft4 and free t3 ft3, the optimal zone is roughly half way between the usual lab normal low high values.
Problems with the assessment of thyroid function in pituitary disease. Note that the normal range for these hormones may change a bit from lab to lab. Luckily, for most people with a normal pituitary, levels of tsh in the blood allow us to sort this out because if free t4 levels are too low for an individual then their tsh production is turned on and levels rise above normal and conversely if free t4 is too high then tsh is suppressed see diagram. 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. Normal range thyroid levels might not be optimal for you. High tsh, normal t4, normal t3 this is the pattern weve been discussing in this post and will usually present with hypothyroid symptoms. Low vitamin d, hi triglycerides, high cholesterol i am vegan and its always been really low until now i. Another reason for low tsh levels and normal free t4 is if you are undergoing t4 treatment for hypothyroidism.
Now, my doctor knows to ignore my tsh readings because they never match the actual readings of my thryoid hormones. Low tsh normal t4 is called subclinical hyperthyroid which means incomplete hyperthyroidism,subclinical means a case of normal body function but blood test results show a little increase or decrease out the normal range, hyperthyroid mean over production of. Therefore free t4 and free t3 levels are important please note that free t3 and free t4 are different than total t3 and total t4. Normal tsh high t3 and normal t4 thyroid cancer nodules. Most patients with a low free t4 but normal tsh simply have lower levels of binding proteins but overall, thyroid function is usually normal. What is needed in this scenario is a tsh, free t4, free t3, and, and rt3. Jan 21, 2019 most labs have normal tsh ranges that span anywhere from 4.
Normal tsh, low t3, high t4, normal free t4 thyroid. It is also important to bear in mind whether total tt4, tt3 or free ft4, ft3 th are. Normal range of tsh,t3 and t4 be beautiful and healthy. Abnormal tft results guidance tsh high t4 normal t3 normal. Thyroid stimulating hormone tsh is released from the pituitary in response to low levels of thyroid hormone. Tsh high t4 normal t3 normal tsh high t4 low t3 low or normal. Screening for interference in thyroid hormone t4 and t3 andor thyrotropin tsh. I started out on armour for about a year but it gave me anxiety and i just never felt right on it. The authors begin by stating that subclinical hypothyroidism is characterized by normal t4, t3, free t4, and free t3 with an elevated tsh.
This guidance is to assist gps in decision making and is not intended to replace clinical judgment. Abnormalities of thyroid hormone metabolism during systemic. It includes those with subclinical thyroid disease, i. It took a long time for my tsh to reflect my thyoid problems. The thyroid gland, therefore, produces less t3 and t4. Pitfalls in the measurement and interpretation of thyroid function tests. Problems with the assessment of thyroid function in. High tsh, normal t4, low t3 this pattern may be an indication that you are having issues with thyroid conversion and. While some conclusions can be drawn from a single test, a combination of test results are usually needed to establish the full nature of your thyroid health. Chances are very high that your free t4 level isnt actually normal even though it may be in the normal range. Tsh levels thyrotropin test, normal, high and low level. To see a comprehensive ebook on thyroid health, click here.
Another possibility is a tumor in the pituitary secreting too much tsh resulting in thyroid. Obtain tsh levels normal low reconsider diagnosis obtain free t. What are optimal tsh levels in hashimotos disease and. From june 2008 until jan 20, i was on 150mcg synthroid. Do you have thyroid symptoms with normal lab results. Free t3 and t4 are usually normal and thyroid hormone supplementation is reserved only for situations of increased tsh, as a consequence of excessive urinary loss of thyroid hormones, or if low t4 is present because of the use of high dose corticosteroids for treatment of nephrotic syndrome.
Endo thinks i have hyperthyroidism because of toxic multinodular thryoid, but the blood work is throwing me off. This means there is an issue with the thyroid gland itself. Nov 20, 2014 so if t4 and tsh look normal on the lab panels, the true problem may never be investigated and the person may go on suffering indefinitely. Hi about your condition it called subclinical form hyptherodism it mean normal t3 t4 and high tsh befor starting treatment you have to chek for thyroid ultasound and thyroid isotop scan and thyroid antibody,after all dr will chose for you sutable treatment.
Problems with the assessment of thyroid function in pituitary. This usually highly suppresses tsh but not everyone perhaps. Honestly, exact normal levels of tsh, t3 and t4 depends on particular pathology lab. Would usually not treat this situation but recheck labs using different lab or different t3 assay test ie, free if. There is no evidence that treating sch results in improved cardiovascular outcomes and evidence is insufficient that it improves neuropsychiatric outcomes strength of recommendation. Download table differential diagnosis of disorders with a high t3, low t4. Why can you have low tsh levels but normal t3 and t4. I cant give you advice over the internet because im not familiar with your case, but generally a high tsh with lownormal t4t3 is considered subclinical, and for me would be an indication to increase thyroid meds, esp. So, yes, you can be hypothryoid and still have normal tsh readings. This in turn means that a level of free t4 near the bottom of normal might be too low for some people who usually live higher in the normal range. If tsh, free t4 and free t3 are within the normal range. But there is a lot of mistaken information about tsh levels, thyroid problems, and how important tsh levels and your thyroid actually are to your overall health and bodily functions. These labs seem at odds, with tsh suggesting overactive thyroid and ft4 underactive thyroid.