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Very low TSH + low T4 Free + High T3 Free (on Cytomel)


I'm new to this forum, and to thyroid problems, and while I was researching information I was always falling back here and read so many great answers from amazingly knowledgeable people, so I thought maybe someone could help me too.

I'm a 35 year old woman and my doctor started to treat me for hypothyroidism about 8 weeks ago. I had many fitting symptoms such as extreme fatigue (my main issue right now), unexplained weight gain, loss of the 1/3 of the outside of eyebrows (weirdly apparently that's a hypo thing!). I also have the genetic predisposition since my aunt, grand-mother, and great-grand-mother were/are all treated for hypothyroidism. Oddly I do not have intolerance to cold but rather intolerance to hot! And a lot! At 23 Celsius I sweat uncomfortably for no reason (but I also take other medicines so it could only be a side effect of those).

Since my doctor started me on Cytomel 25mg my weight stabilized and my eyebrows grew back! However I was still very tired and so he doubled my dose to 50mg. I started then to have some energy and for about a week I even felt "normal", that was amazing! I was so productive!

Unfortunately that also raised my heart beat to the point when I had 164 bpm at rest, and after a little trip to the emergency room a doctor told me to cut back my Cytomel dosage. I didn't want to be tired again (and didn't mind the high heart beat much as the fatigue) so I negotiated to cut only 25% and so I take now 37.5mg daily (1.5 pill).

A few weeks after that incident my doctor sent me for blood test and although I haven't talked to him again yet, I would like to get some help to understand my results which seems very puzzling to me.

Here we go:

   TSH        0.01 mU/L  (range 0.27-4.2),
   T4 Free   6.8 pmo/L  (range 10.5-20.0),
   T3 Free  14.4 pmo/L  (range 3.5-6.5).

Any clue and advice from you would be very welcome. Thanks a lot! :)
6 Responses
649848 tn?1534633700
Your FT4 i way below the range and your FT3 is way too high, which puts the 2 completely out of balance and it's no wonder you don't feel well.

Why did your doctor put you on only cytomel?  That's almost unheard of for hypothyroidism, except in a very few circumstances... Protocol calls for, at least a combination of a T4 medication, such as some form of levthyroxine (there are different brands, depending on your location).

In addition, 37.5 mcg of cytomel is a very large dose and very few people ever need that much... if you were taking a T4 medication with it, presumably, you'd be converting some of the T4 to T3, as well.

Also, are you taking the whole 37.5 mcg of cytomel at one time?  Most of us on a T3 medication find that splitting the total dose into 2 equal doses (usually one in the morning and one at noon) keeps levels more stable throughout the day, since T3 is fast acting so it gets into your blood quickly, peaks and is gone within a few hours.  This could account for some of your remaining tiredness.

Last, but not least, did you take your dosage of cytomel prior to the blood draw that produced the results above?  
Avatar universal
I expect the doctor to alter her dosage.
Avatar universal
Hi Barb,
thank you so much for your very quick answer and detailed information! I really appreciate your help :)

I didn't answered earlier because, well, as you know, I feel terrible these days and incredibly exhausted all the time (despite having seemly good sleep). So, hypothyroid uncontrolled yet I guess...

My Doctor only gave me Cytomel, I am not sure why but my guess would be that he suspected hypothyroidism but wasn't sure (probably because I have some contradictory symptoms such as heat intolerance (I'm totally fine with cold) and fast heart rate). Last time he suggested I alternate my Cytomel with 1 pill one day and 2 the other (1, 2, 1, 2, etc) to have the dose that was giving me energy but while giving some rest to my heart. I followed your suggestion and when I am on a 2 pills day I take the second about 5 hours later to spread the dosage.

I haven't seen any improvement in my energy levels (yet?) but I will be seeing my doctor again on Thursday.

You are asking me a good question, yes I realize now that I did took my Cytomel only about 2 hours before the blood test. Could this make such a big difference in the results? What do you think would be the ideal time to wait for the next test?

Thanks again for your very helpful advice! It is really heartwarming to feel supported <3

I hope my doctor will do as you said and cover the T4 side when I see him on Thursday. This exhaustion is killing my career right now and I can't stay like this for much longer. I hope they will find the right balance for me very soon.
Avatar universal
Barb is away for a while so I will try to provide some of the same good info.  I also cannot imagine why a doctor would have prescribed T3 only.  As a result your Free T4 is terribly low and I expect that your real Free T3 level is too high.  So when you see your doctor you should insist on revising your meds to reduce the T3 dose and add some T4.  You want your Free T4 around the middle of the range and your Free T3 in the upper third of its range, or as necessary to  relieve symptoms.  Symptom relief is the whole objective of going to the doctor in the first place.  If the doctor disagrees, then you should insist on a full explanation of why. to see if you agree or not.  

Assuming that you will have a new set of tests, you should defer taking your morning dose until after the blood draw.  Otherwise, siince T3 acts so quickly, you can get a false high and adversely affect the doctor's decision about meds.  

Also, since hypo patients are frequently too low in the ranges for Vitamin D, B12 and ferritin, those should be tested also.  D should be about 55-60. B12 in the very upper end of its range and ferritin about 70 min.  Inadequate levels can cause symptoms that mimic hypothyroidism.  Low D or ferritin can adversely affect metabolism of thyroid hormone.  

Please let us know how the appointment turns out.
649848 tn?1534633700
Your doctor sounds very inexperienced at treating hypothyroidism...

There's absolutely no point in alternating dosages of cytomel, because it's very fast acting and only stays in your system for a few hours then neutralizes and is gone.  It's not like T4 that builds over time and stays in your blood for up to 2 weeks at a time...

If your doctor "suspected" hypothyroidism, he should have started you on a T4 med that would build in your system over time.  

Symptoms of too much medication (exhaustion, as well as others) can be the same as those of not enough medication....

If you took the cytomel 2 hours prior to the blood draw, your FT3 would be a false high... Cytomel enters the blood stream very quickly and increases FT3 level, but it peaks within 2-4 hrs and is gone a few hours later.  That's why it's recommended that the total daily dosage be split into 2 doses to keep FT3 levels more stable over the course of the day.  So in answer to your question, yes, it could easily have made that big a difference in your results.  

When one takes cytomel, you should try to get the blood draw first thing in the morning and take your cytomel AFTER the blood draw, not before.
231441 tn?1333892766
Agree with Barb.  If you took your meds before the blood draw then the results are useless and reflect a false high.  I would try to get the test redone in this case.
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