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Synthroid, TSH & Free T4 level
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Synthroid, TSH & Free T4 level

This is my first post, I used MedHelp to diagnose my condition(neurocardigenic syncope/postural hypotension) many years ago, and now I am back, seeking for clues.  

So far what I have found for myself, the lab results that are in my hands:
March 2004: TSH-2.89  
Nov 2009-TSH-3.22
Jan 2010-TSH: 3.21, Free T4: 0.98, Free T3: 3.21
July 2010-TSH: 0.94, Free T4: 0.97   (at that time I was under extremely mental stress, with my mom's illness and passing away, that may push my thyroid to or over the edge)
Jan 2011-TSH: 6.17, Free T4: ?    Free T3: ? (I am trying to get copy of this bloodwork, I don't know if Free T4 or T3 was ever tested)

Placed on generic Levothyroxine by my PCP, and feel very sick on it, so I stopped it.  In March 2011, I saw my PCP, she tells me to get back on thyroid medication, and this time, she prescribes brand Synthroid, with dosage of 0.025mg once daily in morning, one hour before breakfast.

I've been on Synthroid since then. I don't feel any difference, if not worse.  I had hypothyroidism symptoms and some other symptoms for many years(goes back to 1999 and 1997-yes, very specific time period--it is long story).

July 2011: TSH-0.83  
September 2011: TSH-0.67, Free T4: 0.66  
Dec 2011:   Had blood drawn Saturday, still waiting for it.

My understanding so far is that with new reference range, anything in range of 0.3 to 3.0 mIU/ML is consider hypothyroidism, and likewise, 0.8 to 1.8 for free T4.

As TSH goes down, free T4 is supposed to rise?  Why is my free T4 keep declines?  What does it may indicates? I read maybe overmedication or central hypothyroidism (points to problem with adrenal or pituitary) or non-thyroidal illness.  

I saw endocrinologist back in October, he say there is no issues with pituitary and adrenal, other than low DHEA, and abnormal high Deoxycorticosterone, and that I should stay on Synthroid as it is. I think maybe he is wrong, I don't know.  

My GYN/OB and reproductive specialist, each independently, ruled out perimenopause because of my FSH and Estradiol level. I am 33.  

My Rheumatologist concurred with me that my rheumatoid arthritis is not responsible for some of my symptoms right now because I no longer have elevated ESR or morning stiffness/trigger fingers in my fingers. By the way I tested weak positive for anti-CCP antibody, and negative for rheumatic factor when i first start to have morning stiffness in June 2010, and I am on Plaquenil since then.  I am negative for anti-thyroid antibodies, and other autoimmune diseases (Srojren's, Lupus, Sarcoidosis, and so on).

I feel much worse now than I feel earlier this year, as time goes by, the more "ill" i feel, i feel so disabling now, with various symptoms piling up, including coming and going low grade fever, chills with or without fevers, and neurological symptoms.  I won't see neurologist until Jan 2nd, referred by my PCP.

Thanks for any insight or pointers.
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649848_tn?1357751184
Let's start here: "My understanding so far is that with new reference range, anything in range of 0.3 to 3.0 mIU/ML is consider hypothyroidism, and likewise, 0.8 to 1.8 for free T4."

No, that's not correct.  Those are the ranges that are considered "normal".

Anything within the range of 0.3-3.0 for TSH is considered normal.  Anything over 3.0 is considered hypo, and anything under 0.3 is considered hyper.

FT4 runs opposite of TSH, therefore, anything less than 0.8 (or whatever range your lab uses, since these vary from lab to lab) would be considered hypo, while anything over 1.8 would be considered hyper.

So yes, ideally, if TSH goes down, FT4 should go up.  Unfortunately, it doesn't always/usually work that way.  

TSH is a pituitary hormone that can vary for a number of reason, even intraday, therefore, it should never be used, alone, to diagnose or treat a thyroid condition.  

Please bear in mind that many conditions are "ruled out" simply because lab results fall in "normal" ranges.  

Doctor do make mistakes, so you should never completely rule that out.

That said, have you ever had, or can you get, a test for Free T3?  This is actual active thyroid hormones and low levels would cause your symptoms.  The FT4 must be converted to FT3, in order to be utilized by the body.  With your low FT4, I would guess that your FT3 would also be low, since there's so little there to convert.  

This could be an indication that your 25 mcg synthroid is, actually, not enough and you are undermedicated.
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649848_tn?1357751184
Let's start here: "My understanding so far is that with new reference range, anything in range of 0.3 to 3.0 mIU/ML is consider hypothyroidism, and likewise, 0.8 to 1.8 for free T4."

No, that's not correct.  Those are the ranges that are considered "normal".

Anything within the range of 0.3-3.0 for TSH is considered normal.  Anything over 3.0 is considered hypo, and anything under 0.3 is considered hyper.

FT4 runs opposite of TSH, therefore, anything less than 0.8 (or whatever range your lab uses, since these vary from lab to lab) would be considered hypo, while anything over 1.8 would be considered hyper.

So yes, ideally, if TSH goes down, FT4 should go up.  Unfortunately, it doesn't always/usually work that way.  

TSH is a pituitary hormone that can vary for a number of reason, even intraday, therefore, it should never be used, alone, to diagnose or treat a thyroid condition.  

Please bear in mind that many conditions are "ruled out" simply because lab results fall in "normal" ranges.  

Doctor do make mistakes, so you should never completely rule that out.

That said, have you ever had, or can you get, a test for Free T3?  This is actual active thyroid hormones and low levels would cause your symptoms.  The FT4 must be converted to FT3, in order to be utilized by the body.  With your low FT4, I would guess that your FT3 would also be low, since there's so little there to convert.  

This could be an indication that your 25 mcg synthroid is, actually, not enough and you are undermedicated.
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Avatar_f_tn
Let's start here: "My understanding so far is that with new reference range, anything in range of 0.3 to 3.0 mIU/ML is consider hypothyroidism, and likewise, 0.8 to 1.8 for free T4."

Oops, thanks for pointing it out...I didn't realize that. I was typing the question at 1am in morning because I couldn't sleep, couldn't think straight, doesn't feel well. It took me more than half hour to type it up..Yikes.  Yes, you are right. What I did meant, anything within range is considered normal, above it, hypo.

FT3-I was tested for it only once I think, that was back in Jan 2010-TSH: 3.21, Free T4: 0.98, Free T3: 3.21-done by naturopath doctor. TSH and Free T3 both is, oddly, exactly the same number-I don't know if that is good or not.

I was designing a website for naturopath doctor at that time, she told me i am hypo, and have adrenal insufficiency as well. She wanted to fix hypo first, she has me try Armour 30mg. It makes me so sick, I took it for 6 weeks. She doesn't believe me, and thinks I was not adhere to the regimen, and says I should already begin to feel better by then.

What's the difference between "Free T4" and "T4"? My lab from Oct 2011 show: TSH: 0.67, Free T4: 0.66, T4: 7.1 (done by endocrinologist, free T3
wasn't tested)

Can hypothyroidism causes coming and going of low grade fever?

Thanks
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Avatar_f_tn
To be more clear, Jan 2010 lab result-
TSH: 3.21 mIU/mL
Free T4: 0.98 ng/dL
Free T3: 3.21 pg/mL  

I didn't realize they are in different measurement units,  both TSH and Free T3 both are 3.21 but in different measurement unit.
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Avatar_m_tn
I am sure Barb will have comments, but I just wanted to ask if you could somehow confirm those results for TSH and Free T3.  I am suspicious that  you might have been given the TSH twice by mistake.  Otherwise it would be a very large coincidence that they are exactly the same..
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Avatar_f_tn
Too late to confirm those results? Um? It is almost two years ago. I'll be sure to ask other primary care doctor later this week to do tests, this time-TSH, Free T4, Free T3, T4, T3, and what else? So to get full clear picture.  

I am very tempting to wean off before stop Synthroid altogether and wait one month(is it long enough?) before repeat test to see where things really stand, start over with a "clean slate" so to speak. A bad idea?

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Avatar_m_tn
Before answering your questions, please have a look at this listing of 26 typical hypothyroid symptoms and tell us which ones you have.

http://endocrine-system.emedtv.com/hypothyroidism/hypothyroidism-symptoms-and-signs.html
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Avatar_f_tn
-Feeling tired (fatigue) and sluggishness (Since 1999, worsen over the years)

-Increased sensitivity to cold (Since 1999, but overall became much better few month ago after I stopped Florinef/Atenolol, and it only came back in last two weeks on and off)

-Joint and muscle pain, aches, and stiffness (Since Spring 2010-stiffness is fine now, but muscles are weak and achy)  

-Pale, dry, rough, and thick skin (Since 1997, along with cystic acne)
-Dry, thinning, or coarse hair (Start in 2003, and stay that way)

-Irregular menstruation-(Since 1997, on BCP for long time, got off it last May, it is okay, cycle alternate between 25ish and 30ish every other month)

-Difficult to exercise (this year, and sometimes it is such labor to cook something simple like pasta*sigh*)

-Decreased sex drive (Not less sexual desires, but lack of physical response down there. Could be due to long use of BCP, I don't know. My GYN/OB thinks it is in my head-I disagreed)

-Slow heart rate (Since 1999 but became better a few months ago after I stopped Florinef/Atenolol. Now it is more faster, stronger.)

-Depression-It is like chicken or eggs.*laughs* Feel sick is making me depressed, not finding answer making me depressed. Not where depression make me fatigued and achy everywhere.

My PCP put me on Zoloft 25mg in 2003 and made me stay on it. She thinks I am having anxiety attack, overreacts to ailments I experienced.  Last year, with my mom’s illness during the summer time I end up get 250mg of Zoloft plus sleep pills from psychiatrist. I was weaning off, then finally done with all psycho-related medications since June, after I got off BCP.  

Not related to hypothyroidism? Low blood pressure, and postural hypotension became pretty obvious in 1999, and was placed on Florinef/Atenolol in 2003.

I have no problem with weight, I am almost underweight for my height, relatively always has been that way since I was little with except of last summer when I really, really overeat(like 10x more) in grief of my mom’s illness and passing. I’ve stopped overeat, and now I am at my normal weight.

I have neurological symptoms that comes and goes.  The last time they happen at such frequency was in 1999. They’ve come back on/off this past fall along with low grade fever, and chills (the kind you get with fever) but without fever.
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Avatar_m_tn
Do you have some suspicion about the original decision to start you on thyroid meds?  Otherwise, I'm not sure what is to be gained from stopping the T4 meds long enough to have a "clean slate".  That would take 5 or 6 weeks, during which you will gradually become hypo, with attendant symptoms that are not much fun at all.  Unless there is some reason to believe that you really don't have thyroid problems at all, then I would go in the opposite direction and get the recommended testing done and go from there.  

Specifically you need current testing for Free T3, and Free T4 (not Total T3 and T4), along with the TSH.    Also, just to be sure, I would also test for Reverse T3.  RT3 is the mirror image molecule of T3, but is biologically inactive.  Sometimes a patient will excessively convert T4 to  RT3, instead of T3.  The result is hypothyroidism, just like having low Free T3.  

Other tests that would be good to have done are Vitamin A D, B12, a full iron panel, zinc, selenium, and magnesium.   Requesting all those tests should definitely get your doctor's attention.  

When results are available, if you would please get a copy of the lab report and post results and their reference ranges, members will be glad to help interpret and advise further.
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