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Doctor insights on: Total Vs Free T4

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Dr. Alan Feldman Dr. Feldman
Internal Medicine - Endocrinology
37 years in practice
Pennsylvania State University College of Medicine
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What do "free t4" & "anti-microsound" mean?

What do "free t4" & "anti-microsound" mean?

Thyroid tests: A "free T4" level is a measure of the biologically active amount of thyroid hormone in the blood, circulating "free" (rather than attached to blood proteins). Anti-microsomal or anti-peroxidase antibodies, are antibodies circulating in the blood stream that are associated with having autoimmune thyroid disease. ...Read more

Dr. Bernard Seif
264 doctors shared insights

Free T4 (Definition)

T4 is the main hormone produced by the thyroid gland total T4 is amount in blood stream attached to albumin, as well as 'free' in blood stream. Free T4 is just the amount free in serum, ...Read more


Dr. David Sneid Dr. Sneid
Internal Medicine - Endocrinology
37 years in practice
Washington University School of Medicine
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What does abnormal to free T4 349829 means?

That number: is outside of the possible range of results for that test, so something is wrong somewhere. Check w/your doctor. ...Read more

Dr. Stanley Schwartz Dr. Schwartz
Internal Medicine - Endocrinology
48 years in practice
University of Chicago Pritzker School of Medicine
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What is the definition or description of: free t4?

What is the definition or description of: free t4?

See below: T4 is the main hormone produced by the thyroid gland total T4 is amount in blood stream attached to albumin, as well as 'free' in blood stream. Free T4 is just the amount free in serum, not attached to albumin. ...Read more

Dr. David Geffner Dr. Geffner
Internal Medicine - Endocrinology
50 years in practice
Georgetown University School of Medicine
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Could you have high total T4 levels but have normal free T4 levels?

Could you have high total T4 levels but have normal free T4 levels?

Yes: Total T4 reflects T4 bound to proteins in your blood. Free T4 measures the amount of T4 that is free and not bound so that it can be metabolically active. Thus women taking Estrogens (as in bc pills) have elevated levels of thyroid binding globulin and elevated total t4, but normal free t4. ...Read more

Dr. Quang Nguyen Dr. Nguyen
Internal Medicine - Endocrinology
years in practice
Midwestern University Arizona College of Osteopathic Medicine
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Can high free T4 level cause lightheadedness?

Hyperthyroidism : Hyperthyroidism can lead to dizziness. Find out the cause for the hyperthyroidism and get it treated accordingly. ...Read more

Dr. Cynthia Villacis Dr. Villacis
Family Medicine
18 years in practice
The Wright State University Boonshoft School of Medicine
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I've been on the same dose of Levothyroxine for 3 years (0.75mcg) & free t4 has always been normal (1.6). Recently, my FT4 was elevated (2.30) Why???

Unsure: If someone has changed the way they take their thyroid medications - if you were taking w/ food and now on empty stomach, if there is a new batch of thyroid meds there can be some variation in potency, less fiber in your diet, lab error, stopping eating soy, herbal supplements, stopping antidepressants or cholesterol meds, taking steroids or being sick --- these can all effect FT4 and TSH levels ...Read more

Dr. Stanley Schwartz Dr. Schwartz
Internal Medicine - Endocrinology
48 years in practice
University of Chicago Pritzker School of Medicine
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What levels of TSH and free T4 do endocinologists follw?

Every lab ..: Different ranges of normal- so both need to be in normal range of that lab. ...Read more

Dr. Michael Kleerekoper Dr. Kleerekoper
Internal Medicine - Endocrinology
47 years in practice
University of Sydney Faculty of Medicine
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Free T4 12.20pmol/l and TSH 1.06 miu/l. How is it normal? Thnx

Thyroid labs: Every medical laboratory has different values for the labs they are doing. Please have your doctor tell you what is the normal range for Free T4 and TSH. If you are in range that's great. If not your doctor has to develop a treatment program for you. Not difficult for the doctor or you. ...Read more

Dr. Vered Lewy-Weiss Dr. Lewy-Weiss
Pediatrics - Endocrinology
24 years in practice
New York Medical College
9

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My free T4 test test reads 0.61 ng/dl with the normal value for the lab being 0.8-1.7. Shouldnt I be treated?

My free T4 test test reads 0.61 ng/dl with the normal value for the lab being 0.8-1.7. Shouldnt I be treated?

Not Necessarily: Your ft4 needs to be assessed when taken into consideration with TSH and other tests. Also, the lab assay for ft4 may be unreliable as in many facilities. Or you might be on other medication interfering in the testing process of ft4. Other tests may be more reliable in assessing thyroid hormone levels if ft4 is persistently low. The direct dialysis method may be helpful. ...Read more

Dr. Randy Baker Dr. Baker
Holistic Medicine
36 years in practice
University of Michigan Medical School
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Aged 62 yrs. Free T4 is 2.38 and TSH is 0.005. what is the dosage of Eltroxcin to be taken?

Aged 62 yrs. Free T4 is 2.38 and TSH is 0.005. what is the dosage of Eltroxcin to be taken?

More details needed: The TSH is low suggesting you have too much thyroid. Different labs have diff. normal ranges so hard to comment on the Free T4 without knowing lab's normal range- might be high, might be low and we can't tell! Also we need to know if you are currently taking Eltroxcin and, if so, how much. In general, it would be wiser to ask the doctor who ordered the test. ...Read more

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Dr. Gurmukh Singh Dr. Singh
Pathology
45 years in practice
University of Pune, Armed Forces Medical College
11
Dr. Louis Krenn Dr. Krenn
Family Medicine
16 years in practice
University of Arkansas for Medical Sciences/UAMS College of Medicine
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What is meant by low TSH high free t4?

What is meant by low TSH high free t4?

Hyperthyroidism: A low TSH and high T4 is an indication of over-active thyroid (hyperthyroidism). This should be evaluated further for any potential cause and discuss treatment options with your physician. Referral to an endocrinologist may be necessary. ...Read more

Dr. David Geffner Dr. Geffner
Internal Medicine - Endocrinology
50 years in practice
Georgetown University School of Medicine
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Can high free T4 detect graves disease?

Can high free T4 detect graves disease?

Not alone: An elevated free T4 is compatable with hyperthyroidism of any cause accompanied by a suppressed TSH and elevated t3 (liothyronine). ...Read more

Dr. Michael Kleerekoper Dr. Kleerekoper
Internal Medicine - Endocrinology
47 years in practice
University of Sydney Faculty of Medicine
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Free T4 is 16.9 pmol/l, TSH 1.08 miul/l gp said all normal. I feel dizzy, and on overdrive.Advise?

High Free T4: The result for free T4 seems quite high to me and could well account for your symptoms. That said, different labs have different reference data so you should ask your doctor to show you the normal range for free t4. ...Read more

Dr. Quang Nguyen Dr. Nguyen
Internal Medicine - Endocrinology
years in practice
Midwestern University Arizona College of Osteopathic Medicine
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Tt in dec. Due to pap. Carc. Thyroglobulin ab doubled since then, and thyroglobulin still under 0.2. Free T4 went from normal to low. Is this normal?

Tt in dec. Due to pap. Carc. Thyroglobulin ab doubled since then, and thyroglobulin still under 0.2. Free T4 went from normal to low. Is this normal?

Thyroid cancer: Thyroglobulin is unreliable in the presence of tg antibodies but the antibodies shouldn't go up. More information is needed regarding size of thyroid cancer and spread to determine if you also need radioactive iodine. Make sure your TSH is suppressed. You might need to increase your current thyroid dose to achieve this. Follow your doctor closely and monitor this. Good luck. ...Read more

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Dr. David Sneid Dr. Sneid
Internal Medicine - Endocrinology
37 years in practice
Washington University School of Medicine
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Can someone define free T4 51.1 and suppressed TSH please?

Can someone define free T4  51.1 and suppressed TSH please?

Something is: Incorrect, as free T4 measurements don't go up that high. If free T4 is above normal and tsp is suppressed you need to be evaluated (and probably treated) for hyperthyroidism. Check w/your doctor and see if there was some sort of clerical error in the free T4 result. ...Read more

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Dr. Stuart Seigel Dr. Seigel
Internal Medicine - Endocrinology
9 years in practice
Virginia Commonwealth University School of Medicine
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My Free T4 is 1.14 and TSH (3rd) 4.27. What does this mean for me?

Monitoring: When a patient is not on thyroid hormone therapy and the TSH is bordeline with a normal free t4 then usually it can be monitored on a 6 month to yearly basis. ...Read more

Dr. Joseph Woods Dr. Woods
Pathology
24 years in practice
State University of New York Upstate Medical University
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Is FREE T4 LEVEL 13 pmol/L normal and my TSH is 0.5 is this normal?

Yes,,: These are technically "normal" values with fT4 normal range being 9-18 pmol/L while TSH is about 0.3-3.0 uIU/mL, though this last range can vary. Best of luck. ...Read more

Dr. Susan Wingo Dr. Wingo
Internal Medicine - Endocrinology
29 years in practice
Uniformed Services University of the Health Sciences F. Edward Hebert School of Medicine
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My free T4 is high 19.30 pmol/l and my TSH is also high 4.530 mlu/l. What does this mean?

My free T4 is high 19.30 pmol/l and my TSH is also high 4.530 mlu/l.  What does this mean?

Few possibilities: These labs seem at odds, with TSH suggesting overactive thyroid and ft4 underactive thyroid. Free T4 tests can be inaccurate in some people who have interfering substances present. Another possibility is a tumor in the pituitary secreting too much TSH resulting in thyroid overactivity, and high thyroid hormone levels. This is quite rare, however. Your doctor can help sort this out. ...Read more

Dr. Scott Lippe Dr. Lippe
Internal Medicine - Gastroenterology
25 years in practice
Mount Sinai School of Medicine
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Dr ordered TSH and free t4. The results are: TSH 4.28 and free T4 1.1. What does this mean?

Dr ordered TSH and free t4. The results are: TSH 4.28 and free T4 1.1. What does this mean?

Thyroid results: It implies that your thyroid may be sluggish but the numbers are different for each lab so you have to include the normal range for that particular lab to have more meaning. ...Read more

Dr. David Sneid
1,407 doctors shared insights

Thyroxine (Definition)

Thyroxine is a thyroid ...Read more