The day before my blood test I didn't eat breakfast until 530 am Answer from Deleted User on reddit.com
The day before my blood test I didn't eat breakfast until 530 am Answer from Deleted User on reddit.com
American Academy of Family Physicians
aafp.org › pubs › afp › issues › 1998 › 0215 › p776.html
Subclinical Hypothyroidism: Deciding When to Treat | AAFP
February 15, 1998 - Because patients with subclinical ... be considered for thyroid treatment. Levothyroxine, in a dosage that maintains serum TSH levels within the normal range, is the preferred therapy in these patients....
American Thyroid Association
thyroid.org › home › patients portal › clinical thyroidology for the public › january 2024 › vol 17 issue 1 p.13-14
Increased FT4 and incompletely suppressed TSH levels are mainly related to levothyroxine use
January 8, 2024 - Patients taking levothyroxine for underactive thyroid have their TSH levels monitored to make sure that their levothyroxine dose is not too much or too little. If the TSH is either low or high, FT4 levels are usually measured next. The authors of this study noticed that when they measured thyroid levels in their hospital, in many patients there was an unexpected pattern: the patients had high FT4 levels even though their TSH levels were normal, not low, as it would be expected.
What causes high TSH but normal T4?
The day before my blood test I didn't eat breakfast until 530 am More on reddit.com
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August 26, 2022Extremely high TSH, normal T4, No thyroid???
Concerns are if I have no thyroid ... with TSH @ 7.380 and my T4 came back as 0.9 What is going on and should I be worried? Endo dr must have my results by now and did not get back to me on what is going on and if my dosage is too high or too low. Should I be worried about anything? Thanks ... @sharibaby17 you sound a bit like my husband. Thyroid cancer was detected by biopsy and his thyroid was removed (2008). After that he has been on Synthroid or generic Levothyroxine... More on connect.mayoclinic.org
High TSH, normal T4.. doc says no med dose change needed.. is that normal?
Something a lot of doctors treating thyroid patients don't take into account is that the lab ranges for someone who is already on thyroid replacement medication is NOT the same as for someone who's undiagnosed and unmedicated. It's a MUCH smaller range, because your levels shouldn't fluctuate as much when at least part of your thyroid hormone levels are artificially regulated. That TSH level is borderline for someone who's unmedicated on whether to start them on meds. That depends on if they're symptomatic and how long their TSH has been that high. For someone who is already on meds, currently available data shows that the overwhelming majority of patients feel closest to "normal" when their T4 is in the top half to top third of the lab range, and TSH is between 0.4-2.5. Levothyroxine is synthetic T4, so people taking levo usually have slightly higher T4 levels than people not taking thyroid medication. I feel like death when my TSH is that high, and don't feel "normal" unless my TSH is <1.5, with my FT4 at the top of the range, and my FT3 at least in the middle of the range. If you're having hypothyroid symptoms and have a TSH over 5 when already on thyroid meds, you need a dose increase. More on reddit.com
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August 12, 2022Normal T4 high TSH
One of the many reasons that TSH trumps the other tests is that it’s a more universal test: meaning, a high TSH does mean your body needs more thyroid hormone, even if FT4 is within range. And if it’s suppressed, even if FT3 and 4 are still within range, that is your body saying there’s too much thyroid hormone circulating. FT3 and FT4 are a lot more particular from person to person. A specific measurement might be within range but actually be too low for your body. You should trust your doctor on this. A TSH of 10 is not a “maybe”. It’s not normal. More on reddit.com
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September 15, 2021Yale Medicine
medicine.yale.edu › news-article › 21-million-americans-may-take-a-hypothyroidism-drug-they-dont-need
Levothyroxine: 21 Million Americans May Take a Hypothyroidism Drug They Don’t Need | Yale School of Medicine
March 31, 2023 - If the level is elevated, they ... TSH is high and Free T4 is low, the provider diagnoses the patient with hypothyroidism. Levothyroxine works by supplementing the low hormone levels with exogenous T4. Some patients, however, have mildly elevated TSH and normal Free ...
Reddit
reddit.com › r/thyroidhealth › what causes high tsh but normal t4?
r/thyroidhealth on Reddit: What causes high TSH but normal T4?
August 26, 2022 -
My TSH is 10.15 (range .5-4.3) and my Free T4 is 1.1 range (.8-1.4) However, I am having many symptoms. I have been in contact with many doctors and they don’t really know what is going on. Does anyone have any suggestions or have been through this situation before? I started 25mcg levothyroxine 5 days ago but since my Free T4 is normal I am doubtful that will help.
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Your pituitary can manage to keep your T4 levels up by constantly poking and prodding your thyroid while it is exhausted. Imagine a factory that has to make 1,000 thing-a-ma-bobs a day. Now say that factory is running smoothly with 50 thing-a-ma-bob assemblers working a normal shifts of 8 hours 5 days a week. Then a few of them quit, or pass away, or retire, or whatever. The manager, Mr Pituitary, gives a speech to the remaining 45 or so worker about putting in a little extra time and working harder to make up the slack. The factory still makes it’s 1,000 thing-a-ma-bobs and everyone manages though they’re a little extra tired. But then, another guy retires, and it’s getting a bit tough, so some guy starts putting in an extra shift each week. Then the assembler putting in the extra shift falls asleep behind the wheel, and now the thing-a-ma-bob factory is down another worker, but they still need to get out that 1,000 thing-a-ma-bobs every day. Then another few assemblers quit because they are becoming unhappy. So the manager, Mr Pituitary, just starts yelling at all the remaining assemblers constantly and insisting they put in 10 hour shifts 6 days a week. The factory is still pumping out those 1,000 thing-a-ma-bobs a day for now, but it can’t keep it up. Soon more employees are going to quit or hurt themselves. It isn’t sustainable. A little levothyroxine will let it relax and work at a more manageable pace.
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This is common with Hashimoto’s which is an organ specific autoimmune disease that affects the thyroid and causes secondary hypothyroidism, which means that the hypothyroidism is caused by the Hashimoto’s. You need a doctor that will treat your symptoms and TSH lab, while also testing your T3 and reverse T3. Some people with Hashimoto’s do well on just T4, some need that and T3.
PubMed Central
pmc.ncbi.nlm.nih.gov › articles › PMC5922674
How to interpret thyroid function tests - PMC
For example, both fractionated ... TH levels. Interestingly, such changes are not generally associated with clinical thyrotoxicosis, and TSH is usually normal....
NHS
nhs.uk › conditions › underactive-thyroid-hypothyroidism
Underactive thyroid (hypothyroidism) - NHS
You may have blood tests to check ... hormone (TSH) and thyroxine (T4) is in your blood. The GP may also refer you to a specialist for more tests. ... An underactive thyroid is usually treated with medicine to replace the thyroid hormone that your body cannot produce. This medicine is usually levothyroxine tablets. You'll usually need to take them for the rest of your life to prevent your symptoms returning. You should be able to live a normal ...
NCBI
ncbi.nlm.nih.gov › books › NBK536970
Subclinical Hypothyroidism - StatPearls - NCBI Bookshelf
February 15, 2024 - In the Thyroid Hormone Replacement ... placebo-controlled trial, 737 adults who were aged 65 or older above with subclinical hypothyroidism (TSH between 4.60 and 19.99 mIU/L and free T4 within the reference range) were included....
RACGP
racgp.org.au › afp › 2012 › august › hypothyroidism
RACGP - Hypothyroidism - Investigation and management
April 9, 2012 - AetiologyIodine deficiency remains the most common cause of hypothyroidism worldwide.4 However, in Australia and other iodine replete countries, autoimmune chronic…
MedlinePlus
medlineplus.gov › home › medical tests
Thyroxine (T4) Test: MedlinePlus Medical Test
TSH tells your thyroid how much hormone to make. Normally, if your T4 levels are too low, your pituitary makes more TSH to make your thyroid work harder. If your T4 levels are too high, your pituitary stops making TSH.
UCLA Health
uclahealth.org › medical-services › surgery › endocrine-surgery › conditions-treated › thyroid › normal-thyroid-hormone-levels
Normal Thyroid Hormone Levels - Endocrine Surgery | UCLA Health
Thyroid Hormone Treatment Levothyroxine is the standard of care in thyroid hormone replacement therapy and treatment of hypothyroidism. Levothyroxine (also called LT4) is equivalent to the T4 ...
SingleCare
singlecare.com › home › how do you adjust levothyroxine if tsh is high?
Steps to adjust levothyroxine if TSH (thyroid stimulating hormone) is high
November 4, 2025 - Generally, a TSH between 0.5 and 4.5 mU/L is considered normal, but some labs may define it differently. If a patient’s TSH is flagged by the lab as abnormal at 4.0 mU/L, for instance, a doctor may or may not feel it is necessary to increase ...
Medical News Today
medicalnewstoday.com › articles › hypothyroidism-with-normal-tsh
Hypothyroidism with normal TSH: Causes and treatment
December 18, 2023 - A thyroid function test measures levels of thyroid-stimulating hormone (TSH) and thyroxine (T4) in the blood. This is also called “free” T4. Generally, high TSH can indicate hypothyroidism, while low TSH can indicate hyperthyroidism, though the levels and severities of these can vary.
British Thyroid Foundation
btf-thyroid.org › subclinical-thyroid-disease
Subclinical thyroid disease
Learn about subclinical (borderline) thyroid conditions
Mayo Clinic
mayoclinic.org › diseases-conditions › hypothyroidism › diagnosis-treatment › drc-20350289
Hypothyroidism (underactive thyroid) - Diagnosis and treatment - Mayo Clinic
December 10, 2022 - Understand what happens when your thyroid is underactive and learn about treatment for this condition.
American Thyroid Association
thyroid.org › home › patients portal › clinical thyroidology for the public › february 2023 › vol 16 issue 2 p.3-4
Overtreatment and under treatment of hypothyroidism with thyroid hormone is associated with increased death from heart disease
February 17, 2023 - Hypothyroidism is treated with thyroid hormone replacement, usually in the form of levothyroxine. The goal of treating hypothyroidism is achieving a TSH in the normal range, which is usually sufficient in relieved the symptoms of hypothyroidism. However, it is important to not over or undertreat the condition. If a TSH remains high on levothyroxine (undertreatment), the patient is likely to have continued symptoms.
PubMed Central
pmc.ncbi.nlm.nih.gov › articles › PMC8006411
The Stability of TSH, and Thyroid Hormones, in Patients Treated With Tablet, or Liquid Levo-Thyroxine - PMC
After the diagnosis of hypothyroidism the usual therapy is tablet levothyroxine (L-T4), with a monitoring of the thyroid-stimulating hormone (TSH) level in primary hypothyroidism every 6–8 weeks and L-T4 is adjusted as necessary to reach an euthyroid state. Once TSH is stabilized in the normal range, it is recommended to conduct annual testing in the treated subjects to warrant suitable replacement.
Medscape
emedicine.medscape.com › tools & reference › endocrinology
Hypothyroidism Treatment & Management: Approach Considerations, Hypothyroidism in Pregnancy, Subclinical Hypothyroidism
A study of athyreotic patients (patients without a functional thyroid gland) found a high heterogeneity in these patients’ ability to produce T3 when treated with LT4. Approximately 20% of these athyreotic patients did not maintain normal free T4 or free T3 values despite a normal TSH.
Cleveland Clinic
my.clevelandclinic.org › health › diagnostics › 24235-thyroxine-t4-test
T4 (Thyroxine) Test: What It Is, Function, Purpose & Levels
July 21, 2025 - Healthcare providers prescribe a synthetic form of thyroxine called levothyroxine to treat hypothyroidism (underactive thyroid). They can also prescribe it to treat some kinds of thyroid cancer alongside surgery and other treatments. Healthcare providers may use T4 tests to assess how well your thyroid is working. Your provider may order a T4 test (in addition to a TSH test) for any of the following reasons:
Mount Sinai
mountsinai.org › health-library › report › hypothyroidism
Hypothyroidism Information | Mount Sinai - New York
This drug helps normalize blood ... T4, and triiodothyronine (T3). Continuous treatment with an adequate dose of levothyroxine will also normalize TSH levels. Many prescription medications and dietary supplements can interact with levothyroxine and either increase or decrease its potency.
Mayo Clinic Connect
connect.mayoclinic.org › discussion › extremely-high-tsh-normal-t4-no-thyroid
Extremely high TSH, normal T4, No thyroid??? | Mayo Clinic Connect
May 23, 2022 - Hi, Why was your dose of Levothyroxine increased if your TSH was high at 6.44. That makes no sense as increasing the dose would only make you hyper. No wonder you are losing body fat. A reading of 28.0 is needing help with this immediately. I wish some doctor's would listen to patients.