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Difference between T4 in synthroid and armour/nature throid
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Difference between T4 in synthroid and armour/nature throid

Is there a difference between the T4 in Synthroid and in Nature Throid/Armour?  I was just switched to Synthroid and I'm feeling the difference.  All the hypo symptoms are back with a vengence with in 4 days.  Took Nature Throid dose to get thru the day.  How long does it take for Synthroid T4 to start converting to T3?  Is going from 130mg nature Throid to 137mcg of Synthroid normal?  It is less T4 that I was getting on NT.  Can anyone help me with this?  I feel like I'm going crazy.
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798555_tn?1292791151
I dont believe the conversion chart on the NT site is correct.

I was on 137mcg levothyroxine like synthroid this spring. Went to Armour, then generic armour 130mg a day like you ( but a little more 2 days a week). Did fine.

Been on NT now for 1-1/2 weeks at the same dose, and I might need a little more (like others said).

If you still can convert t4 to t3, your thyroid might have gotten lazy in doing so with the dessicated. Your not getting that extra T3 you were used to. You may snap out of it, or you might need a SMALL dose of cytomel, like 5 or 10 mcg per day. The cytomel is stronger feeling for most people than the T3 in dessicated.

If synthetic does work for you, it will take time and you may not feel right for some time. It was hard for me to switch from sythetic to dessicated, feel OK now. First month was difficult.
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Avatar_m_tn
According to this conversion chart I've used, I think 130 mg ov Nature-throid is more like 200 mcg of Synthroid.  Also, I would not make the change all at once, because of the T4 to T3 conversion issue.  To my knowledge, there is no set timeframe for something like this, but I if possible, I would make the change 1/4 of the dose at a time over about 4 weeks, to try and prevent any adverse reactions.

By the way, why were you changed to Synthroid?

http://thyroid.about.com/library/drugs/blconversionchart.htm  
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Avatar_f_tn
Family is against dessicated (because it didn't seem to be working for me and mainstream medical says use synthetic) and to get them off my back I agreed to try synthroid.

Dr. said to change all at once which I disagree with but I'm trying to be a good little patient and do as she says since my DH is giving me grief and is very concerned.  Dr. said 130 NT = 200 Synthroid which no one needs to be on.  Said my hypo symptoms Friday could not be related to changing meds and much less T3. Dr. Bro-in-law said T4s might be chemically different between NT & Syn therefore feeling like detox coming off NT and having to wait 4-6 weeks for Syn to ramp up.  Ever hear of chemical difference?  I though T4 was T4 where it came from human, pig or synthetic?  Very confused now.

History -
43 years old. Hashi diagnosed in 2/2007, partial TT 4/2006 (negative for suspected cancer) on Armour 75 mg to 120 mg increasing does from 4/06 to 8/09.  Changed to Nature-Throid 8/09 130mg in morning.  Numbers fluxuate greatly and I feel like crap.  Any suggestions?  Endo just changed me to synthroid 137mg on 12/14. She is willing (she says) to add T3 is need be. Says can't regulate on T3/T4 mix and low TSH means will get a-fib and osteo.  Labs to be run 1/18/10 to check TSH, FT3 & FT4.  Very scared I'm going to go truely hypo.  Bone scan great 2 years ago. High cholesterol ranging from 222-305 since 8/2001. Sometimes the dr. or lab didn't run the FT 4 as requested.  Any suggestions?  Family is against dessicated and to get them off my back I agreed to try synthroid.
TSH FT4 FT3
0.29 1.14 457
2/3 of my thyroid removed
0.48 ? 295
1.6   ? 260
1.04 0.8 236
0.21 0.82 224
<.04 ?  313
25.23 ?  190
0.13 0.94 356
0.08 ?  317
0.88 ?  289
0.11 0.86 330
0.11 0.76 201

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Avatar_m_tn
Need to know the ref. ranges your lab uses for those FT4 and FT3 results.  Results vary from one lab to another so it is important to know where your results fall, within the ranges.  I also think you will get some good info from this post I made today to  another member.  



In my opinion, the very best way to treat a thyroid patient is to continually test and adjust the levels of the actual, biologically active thyroid hormones, which are free T3 and free T4 (FT3 and FT4, not total T3 and total T4), with whatever type of medication is required to alleviate symptoms, without being constrained by resultant TSH levels.  Relief of symptoms is all important.
FT3 is actually the most important thyroid hormone because it is at least four times as active as FT4, and FT3 largely regulates metabolism and many other body functions.  FT3 also has been shown to correlate best with hypo symptoms.  TSH is a pituitary hormone that is affected by many variables and it does not correlate very well at all with hypo symptoms.  Many members here have reported that full symptom relief has required that their FT3 level had to be adjusted into the upper part of its range and FT4 adjusted to at least the midpoint of its range.  
The key is finding a good thyroid doctor that will treat your symptoms by testing and adjusting your FT3 and FT4 levels.  If your body adequately converts T4 to T3, then you can be successfully treated with  a T4 only type med, which is usually the easiest approach.   If not, then you may need to consider meds that will allow you to adjust the T3 level independently from T4, such as a dessicated T4/T3 combo med, or even a combination of a T4 med and a T3 med such as Cytomel.  





When making a switch from dessicated T4/T3 med to Synthroid, there is definitely an effect from the sudden loss of T3.  Don't know how long, but there will always be a time lag until your body is adequately converting enough T4 to T3, to replace the amount you lost from the Armour.    That's why you felt the hypo symptoms right away.

T4 is T4, whether it is from the Armour or the Synthroid.  As far as low TSH making you hyper, that is wrong.  You are hyper only if you have hyper symptoms.  It is very common for a thyroid patient on medication to have TSH suppressed to the low end of the range or below.  This should be a concern only if it is due to excessive levels of FT3 and FT4, causing you to be hyper, which apparently was not the case.  

As far as a low TSH being a concern for A-fib and osteo, that is a misconception as well.   The lack of TSH (a pituitary hormone) cannot cause A-fib.  If A-fib is related to thyroid, it would be due to excessive levels of the active thyroid hormones, FT3 and FT4. not to the absence of TSH.  TSH is affected by many variables, including the time of day when blood is drawn.  Unfortunately many doctors prescribe to the "Immaculate TSH Belief", and incorrectly promote some of the things you were told.

As far as Osteo is concerned, many studies have shown that thyroid hormone is not a direct cause for bone loss.  If the conditions for bone loss already exist, then increased metabolism occurring from thyroid replacement hormone would only increase the rate of loss.  The correct way to treat this condition is to eliminate the cause for bone loss, not withhold thyroid medication.

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Avatar_f_tn
Thanks!!!

I think this endo and I are going to part ways.  I'm very upset that that she was saying it can't be the reduction in T3, must be something else & to tough it out.

Any idea why the last tests show below range in all three tests?  

Ranges - TSH = 0.35 - 5.50
FT4 - 0.89 - 1.76
FT3 - 230 - 420
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Avatar_m_tn
When were these last labs done relative to your change to Synthroid?
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Avatar_f_tn
TSH - 0.11
FT4 - 0.76
FT -  201

Ranges - TSH = 0.35 - 5.50
FT4 - 0.89 - 1.76
FT3 - 230 - 420

Labs were run on 10/23/09.  I started Synthroid 12/15/09.

By the way.  I have felt more energy since I've been on Syn. A bit more aches in the joints and don't sleep as well but haven't had another crash since the 18th.  I go to my new regular dr on the 31st and I'm hoping I can work with him on this instead of the endo.  Insuranace is changing and she will be twice as expensive to see starting in 2010.  Add that to the not believing me and I'm too happy with her right now.
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Avatar_m_tn
I'm a bit surprised that your FT3 and FT4 levels were that low while taking 2 grains of Nature-throid.  I also would have expected that TSH would be a bit higher, but it is frequently suppressed when on medication, especially one containing T3.  Were you having hypo symptoms during the earlier times when your FT3 was in the upper part of its range?

I'm also surprised that you are not having more hypo symptoms since the complete change to Synthroid on 12/14.  You won't see the full effect on hormone levels until the last week of Jan.

It is too bad that you were getting such poor info from the Endo.  I hope your regular doctor will work with you to treat your symptoms, by adjusting the levels of FT3 and FT4, as required, without being constrained by resultant TSH levels.  You might find interesting and useful to discuss with your doctor, the info in the following email that I have sent to the Amer. Thyroid Assn. twice.  Unfortunately, no answer.  Please keep us up to date on test results and symptoms.







After having gone through years of not being treated for hypothyroidism, because my TSH was 4.97 and thus "normal", I was very pleased to note that the AACE had finally recognized that the range was incorrectly determined.  After removing some suspect hypo patients' data, and recalculating the range, they recommended it be lowered and narrowed to .3-3.0.  Six years after this recommendation, why is it that most labs and doctors still do not recognize the change and still use the old range?  Since doctors also over-rely on TSH as the gold standard for thyroid testing, multitudes of hypo patients are still being told they are "normal" and do not get treated.  Is the ATA doing anything to encourage the medical community to change this practice?   If so, why is it taking so long?

My second concern is that doctors predominantly rely on TSH in determining a patient's thyroid status.  Why is this, since TSH is a pituitary hormone that is affected by so many variables, including even the time of day when tested?  Why not promote more widespread use of the actual thyroid hormones that are biologically active (FT3 and FT4) and that largely regulate metabolism and many other body functions?  From studies I have seen and much personal experience, TSH does not even correlate very well at all  with  hypo symptoms.  The test that has been shown to correlate best with hypo symptoms is free T3.  Yet there are very few doctors that order a FT3 test as a matter of course, and some that refuse to order one at all.

When FT3 and FT4 are tested,  the ranges are so broad that patients with overt hypo symptoms will usually still fall in the lower end of the current range.   As a result they are also told they are "normal" and receive no treatment.  Why haven"t the reference ranges for FT3 and FT4 been corrected like TSH, to exclude suspect hypo patients?  If this were done, these ranges would be raised and narrowed,  comparable to the change for TSH.  I'm sure that some would say that the ranges for FT3 and FT4 are just reference ranges, and that as you approach the lower end of the range, the probability of being hypo goes up and that in those cases, doctors look further to determine if medication is advisable.  I agree that this should be the case but I assure you it isn't.  Labs and doctors interpret results within the reference range as "normal" and don't want to go any further.   As a result of all this the above  misunderstanding and misapplication, millions of patients go untreated and remain miserable with their hypo symptoms.

Is the ATA doing anything to raise the awareness  of these problems among the medical community so that we hypo patients can look forward to some positive changes?  If you are not, then I cannot imagine any other organization that could do the work necessary to coordinate changing the awful mess that exists in the area of diagnosis and treatment of thyroid patients.  Your response will be greatly appreciated.

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Avatar_f_tn
The extemely low reults on FT3 & FT4 as well as TSH were what was concerning me while on 2 grains.  I think I felt pretty hypo the whole time I was on dessicated.  I had period where I felt better but I wasn't keeping a log so I don't know the correlation to dosages.  I'm keeping a log now I can tell you that!

I felt horrible the first week on Syn but after I took 2 grains of Nature Throid on Friday the 18th in addition to the Syn I felt normal again after 2 hrs.  After that I was okay as I said except for some joint pain that is still there.  I go for labs on the 18th as well as an ultra sound of thryoid.  New, non-endo, dr. wants a scan since one has not been done since surgery in 2006 for the suspected cancer.  I'll also get labs for anti-thyoird antibodies to see if it was Hashi's.  Having a hard time going to sleep these days though since I have more energy.  Not jittery or over medicated, just awake and aware.  The new dr said he treats based on symptons and free T labs and not so much TSH.  He'll also give synthetic T3 if needed.  Thanks for all your info.  It is so nice to talk to someone that actually understands this.
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Avatar_m_tn
I like what the new doctor said about treating symptoms.  Please keep us tuned in to your progress and what you think about the doctor after your appointment.
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734073_tn?1278899925
Hi,  thought you might like to know that sometimes people do better with a little more Nature-throid then Armour then the conversion chart says. Maybe instead of switching to Synthroid, what you need to do is raise your Naturethroid by 1/2 a grain and if still hypo after a few weeks then go up an additional 1/2 a grain. My daughter is nine and born without a thyroid gland. She cannot take Syntroid as she does not convert it into enough t3 and has lots of health issues when on it..We switched her to Armour 2 grains last spring and had to switch to Naturethroid at the end of summer due to reformulation isssues w/Armour. However, it has taken her 1 grain more of it to be symptom free. She takes 3 grains per day. 1 at 7:00 am, 1 grain at 11:00 am and the last grain when she returns home from school at 3:00. It has been 5 months and she is doing very well now in every way! I suggest you go back to the doctor who had you on Naturethroid and try a little higher dose to see if your hypo. symptoms improve and if your freet3 and freet4 will come up some in their ranges. I bet you'll feel better  as my daughter now does. Good luck and God bless!
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Avatar_f_tn
Thanks.  I had committed w/ my family to try Syn since I couldn't get regulated on Armour or Naturethroid.  So far it has been better except I am having alot of aches and pains in my joints.  I went 1/18/10 to have labs drawn to test for everything as well as an ultrasound.  They couldn't find the thryoid!  2/3 was removed in 06 and the rest must have atrophied since I have been on basically supressive does since then. At least she didn't see any nodules this time.  I cannot wait to find out the lab results, hopefully by the end of the week. When I took 3 grains of armour or Nature Throid my hands would really shake and I didn't feel any better.
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Avatar_f_tn
Interestingly enough my cycle has extended as well (or I'm pregnant!)  I did test though and it was negative.  Usually I go 18-24 days & I'm at about day 26 now.
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734073_tn?1278899925
My daughter had severe joint pain in all joints when her free t4 dropped into the lower 1/4 of the reference range on the reformulated Armour last August. I switched her to Nature-Throid and increased her dose slowly until the freet4 was in thye upper 1/2 of normal range with her freet3 a little higher and "WaLa'- her joint pain went away! She is not hyper in any way and feels good again. She is nine and born without a thyroid gland. Since you now have no gland, maybe getting your levels a little higher will be the answer for you too. I can't help you with the period as this struggle for my daughter is yet to come. It scares me to death for her and is why I am determined to figure out where she feels best now before we add in puberty and those hormones to the mix. I would make a seperate post for this topic if I were you and I bet you'll get some hits on it. You should order the book "Overcoming Thyroid  Disorders" by Dr. David Brownstein. You can get it on Amazon.com. It was a big help to me and an easy read.
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393685_tn?1325870933
If you feel better on the synthetic 134mcg Synthroid - but are still experiencing the aches of hypothyroidism - you may be one of the patients you cannot tolerate the ratios of hormones in the Armour or Naturethroid ( 2 seperate medications) and need to stay on a balance synthetic T4 medication..... adding in a low dose of a T3 maybe - like Cytomel.

Its all about tweeking the meds and if you are finding better results on what your are doing - but need a little more - your doctor does have the option of giving you some of that T3 med you may need to feel just great.

Talk to your doctor about trialing you on a T3 Cytomel - maybe a very small dose of .5 mcg and "track" your symptoms... If you develop a log of things with meds - labs and symptoms  - its easier for your physician to know exactly where you need to be sometimes and what is working best!.
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734073_tn?1278899925
What's up? Please email me the 2010 questions again as I accidentally deleated them, oops! How is the Erfa doing for you? All's well here. Call me when you can so we can catch up. Miss ya!
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393685_tn?1325870933
miss ya too - Ok
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Avatar_f_tn
I have kept a log since starting Synthroid which I ready about doing here on the site. The Dr. said he would give me T3 if needed.  Hopefully he will now. He dosen't like my TSH being this low (see labs below) & wants to lower my dose which will leave me even less T4 to convert to T3 (I think).  I just emailed him several questions so hopefully I'll hear back from him soon.

Just got my labs back after a month on Synthroid

TSH - .02 range .34-5.60
FT3 - 3.46 range 2.39-6.79
FT4 - 1.48 range .58-1.64
Cholesterol - down from 250 to 211
Glucose - down from 93 to 87
Anti Thymoglobulin  - 40 range 0-40
Anti Thyroid PeroxAB  -55 range 0-40

Dr., of course, wants to lower Synthroid from 137 to 125.  I want him to leave it and add T3 or at least add T3 if lowering it. Waiting on email response from him about adding T3. Lots of aches and hair dropping out which I think/hope T3 will help.  I wonder if I need more time at this dose 137, for my body to adjust to converting T4 into T3.  Ultrasounds was good, no nodules, but atrophied since I have basically been on supressive dose since having thyroid partially removed. I had a bone density test 2 years ago and it was great.

Any suggestions on what I can say to the dr. so he won't lower my dose?  Thanks!
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Avatar_f_tn
Well I just got a call back from his office.  He is willing to keep me on 137 to see if the FT3 comes up any more and then run labs and discuss.  He threw out the old "osteo problem developing from low TSH" and "it's dangerous to have too low a TSH".  I will go with that for now and see if it gets any better in 6 weeks.  I doubt it but I can live like this for 6 weeks and that way I will seem like I am trying.  I'll even request the bond density test again to see if I have had any kind of loss while on suppressive dose.  Not sure what else to do.  Any suggestions?
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Avatar_m_tn
I switched to NatureThroid a week ago and my blood pressure seems to be high.  Foggy in my head, ringing in my ears.  My T4 dropped to 5.4 (range 4.5-12) on the reformulated Armour and my doctor said this was normal.  I requested Nature Throid and he gave it to me but ever since I have been on it my blood pressure seems to be high.  Does low T4 cause and increase in BP.  Also, I am unable to sleep as well,
don't feel hyper but somewhat awake and not in REM sleep.  Is this indicative of too much T3 or a side effect of Nature Throid?  I have brain energy but no physical energy.  Lots of join pain, unbearable pain.  I get the same comments from my dr. as some of the others like TSH is something to be worshiped and we need no other test.  Any advice?
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Avatar_m_tn
P>S> forgot to mention my body temperature this morning was 95.8.  It has been low since I went on Armour but this is the lowest so far.  I never get enough T4, i think.
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734073_tn?1278899925
95.8 is a very low body temp. and a sign of being low metabolic or hypOthyroid. As well as the severe joint pain, brain fog, and sleep issues. Are you fatigued and tired in the morning ( hard to get up and get going?) As far as the ear ringinging, we've thankfully never experienced this, however, I have seen people on here who have this symptom. Blood pressure I'm not sure about, but you can make a new post about this and see. You do know that the Armour thyroid and the Nature-Throid have both been reformulated? The new Armour was reformulated first and it caused many to begin having symptoms of hypothyroidism who had been on it for years and had always done great until they changed the ratios in the fillers/binmders to include more celulose and less dexstrose. This really messed up the med for many. Lots of people then switched to Nature-Throid and it began to be hard to get (rumor it was a supply and demand issue). Now it is finally showing up again- problem is, it has been changed now too! We have not tried it yet, however I'm afraid the changes made are very similar to Armour changes so I am leary. I'm not hearing alot about it yet, however there are some who have tried it and are having difficulties with a low t4 on it. It is so frustrating! Many people have switched to Erfa Thyroid from Canada and are doing great as it is very similar to the old good Armour. There is also compounding pharmacies for desiccated thyroid that many are using. Or you can get back on synthetic t4 like Synthroid and add t3 synthetic cytomel to it several times per day. These are about the only options. Maybe just a slight increase in the Nature-Throid is needed. If your Nature-Throid pills have a scored line down the middle then you know that you have the new stuff. You look hypothyroid to me based on labs and symptoms so you need to get that  freet4 and freet3 higher in the range. You did not list your freet3 level and this is the level that is most representative to symptom relief as it is the active hormone that the body must have. t4 is a storage hormone that must convert to t3 within the body. Desiccated thyroid has both t4 and t3 in it so the body is not as burdoned by the conversion process. As far as TSH goes, that is just a pituitary signal sent to tell the thyroid gland that more thyroid hormone is needed in the brain and body. It is not the gold standard any longer for treatment. Tracking the freet3 and freet4 is better and most feel better when the freet3 is higher in normal range with the freet4 slightly below Free t3 at mid range or slightly higher. If your doc doesn't get this, then find a new one who does and can get you well. I hope I've been of some help to you. My daughter is nine and born without her thyroid gland so I have a little experience here and I have no brain fog as I have no thyrouid issues so I've been able to be her advicate . It is hard when you are the one who is sick and then have to figure all this out, especially if you have a doctor who is very wester medicine and is not up to date with testing, ranges, meds. and symptoms. Educate yourself as much as possible so that you can get on the road to recovery! God Bless!
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Avatar_m_tn
I just started Nature Throid as my first hypothyroidism med. two days ago. How long should I wait to know if this is working for me? I still have every symptom, achy joints, fatigued, weight gain, etc. Thanks!
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734073_tn?1278899925
Hi! I take it that you are on the New (reformulated) Nature-Throid? What med were you on before for hypothyroidism and at what dose? What dose are you on with the Nature-Throid? It will take more then two days for sure. The thyroid hormone must get into the cells so it takes a little while. Symptom relief can then begin, however you must be on the right dose and the right med for you. Blood levels can be taken in 4 to 6 weeks to see if you are on the right track. Try to get extra sleep, as this helps speed things along. You can also take suppliments like magnesium, Omega 3, and vitamin D and a good multi. Eating correctly ( low carb. high protein, low sugar and avoid processed foods) can help too. We are doing gluten free and organic and it has really made a difference in how well we feel over-all. We have not tried the new Nature-Throid yet, so I really don't know how well it will work for my daughter. The old Nature-Throid has been great for her. Please keep me posted on how you are doing with the new stuff. It did take 1 grain more of the Nature-Throid then the original Armour for my daughter to get symptom relief. We upped her by 1/2 a grain twice at two week intervals, and it took aprox.1 month for symptom relief to really begin for her at the higher dose. Her blood work shows TSH close to 0 and her freet3 high in the range and her freet4 slightly lower then t3 but above mid range (higher side). She feels great and has no symptoms of hypo or hyper. Keep in touch on your progress with the new Nature-Throid as we will need to make a decision as to give it a try or not in the near future as my daughter has no thyroid gland and we will eventually run out of our supply of the original NatureThroid. i want to be as informed as possible as to what to expect with the new formula, before we must cross the bridge of what to do next for her best health possible. God Bless and good luck!
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