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Increase in Levothyroxine Dosage, Decrease in Free T4
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Increase in Levothyroxine Dosage, Decrease in Free T4

Hello. I am a 36-year-old male.

In July 2009, at age 35, I was diagnosed with hypothyroidism. My blood test showed a TSH of 147.3 (normal range = 0.35 - 5.5). A second blood test showed a TSH of 122.494 and a free T4 level of 0.16 (normal range = 0.71 - 1.81).

My subsequent blood tests were as follows:

after 6 weeks of 50-mcg levothyroxine: TSH = 90.383, Free T4 = 0.46

after 7 weeks of 100-mcg levo: TSH = 15.802, Free T4 = 0.77

The doctor then increased my levo dosage to 125 mcg. After three days of 125-mcg levo, I felt some bad side effects (extreme drowsiness, pain in my left armpit). So, I went back to the 100-mcg levo. After 9 days of 100-mcg levo, I felt that my hypothyroidism symptoms were coming back. So, I went back to the 125-mcg levo. The 125-mcg levo alleviated the symptoms.

After 6 weeks of 125-mcg levo, my blood test was as follows:

TSH = 3.461, Free T4 = 1.05

I continued taking 125-mcg levo for the next 8 weeks. For the first 2 of those 8 weeks, I took Coldeeze lozenges and Robitussin DM for a cold. For the first 4 of those 8 weeks, I took Centrum multivitamin from time to time. I took the Centrum late at night with dinner (to avoid interference with the levo in the morning). The Centrum gave me chest pains and other discomfort. So, I stopped taking the Centrum. After I stopped taking the Centrum (and during the last few weeks of this 8-week period), my hypothyroidism symptoms came back (soreness in arms and legs, other symptoms).

After that 8-week period of 125-mcg levo, my blood test was as follows:

TSH = 1.919, and Free T4 = 1.11

After 7 weeks of 137-mcg levo, my blood test was as follows:

TSH = 1.016, Free T4 = 1.10, and Free T3 = 3.5 (normal range = 2.3 - 4.2).

So, even though my levo dosage was increased, my Free T4 slightly *decreased*. Meanwhile, my hypothyroidism symptoms have been bad. I have been feeling tingling in my hands, soreness in one or both knees while walking, sensitivity to the cold, etc. I think I feel worse now than I did when my TSH was 15.

So, if the levo increases and the Free T4 decreases, does that mean that my thyroid gland itself is getting worse? Or, did the Centrum somehow blunt the effectiveness of the levo? Or, has the levo simply outlived its usefulness to me? Should I switch to the brand-name Synthroid or the brand-name Levoxyl?

Thanks for any help.

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the decrease in FT4 is only a slight one. Your FT3 looks like it's coming up nicely...but you may still need a dosage increase of levo since you still have symptoms. What is the cause of your hypo? It's true that some people feel better on Synthroid. Just my opinion, but looks like you need a dosage increase. I would talk to the doc and tell him/her whats going on :)
It would be nice to see a period in which you aren't changing things, such as the addition/subtraction of the cold med(s) or the centrum.  

I agree that the drop in your FT4 is minimal and with your FT3 up like it is, you apparently don't have conversion issues.  

It's possible that you need just a "tweak" to your med to help alleviate symptoms.  In addition, some meds have fillers or other ingredients that causes patients to be less tolerant of them.  Some do well only on synthroid; others (like myself) do better on generic.

Also, don't forget that some symptoms can "cross over" and apply to either hyper or hypo.  You  might also want to look into vitamin/mineral deficiencies, such as vitamin B12 and D.

Have you been tested to confirm/rule out Hashimoto's Thyroiditis?  This is an autoimmune disease, in which, antibodies slowly, but surely, "kill off" your thyroid.  Since we are all affected differently, this process can be faster for some, slower for others. Hashi's can also make hypothyroidism harder to control.  

An ultra sound would also be helpful, as that could tell whether or not you have nodules on your thyroid.  

Talk to your doctor and ask for the antibody tests - TPOab (thyroid peroxidase antibodies) and TGab (thyroglobulin antibodies), if you haven't already had them.  
I stopped taking Centrum in early February 2010. Since mid-January 2010, I have not taken Robitussin at all, and I have taken Coldeeze lozenges very rarely (maybe only a few times).

I took a blood test around February 20, 2010. My blood test showed TSH = 1.919 and Free T4 = 1.11. During the two weeks before this blood test, I had not taken any Centrum at all. During the month before this blood test, I had not taken Robitussin at all, and I might have taken a few Coldeeze lozenges at most. During the 14 weeks before February 20, 2010, I took 125 mcg of levo.

Starting on March 4, 2010, I took 137 mcg of levo for 7 weeks, with no Centrum at all, with no Robitussin at all, and with only a few Coldeeze lozenges at most. My TSH went down to 1.016, but my Free T4 slightly went down to 1.10.

A week ago, I saw an endocrinologist for the first time. I mentioned my blood-test and levo-dosage history to him, and he suggested that maybe I should switch to Synthroid or Levoxyl.

The endo believes that TSH is the best indicator of thyroid-hormone amounts. He believes that Free T4 can vary from hour to hour. However, I did point out to him that, last summer, I had a TSH of 147 and, a few days later and without any thyroid medicine, a TSH of 122. So, TSH can vary as well.

As for "tweaking" my dosage of levo, my symptoms came back in February 2010, the dosage was raised to 137 mcg, and my symptoms have not been alleviated. So, that might suggest that a different medication is in order.

My TPOab was 3.0 (negative), and I will have the test for thyroglobulin antibodies in my next blood test. If I have Hashimoto's, does that mean that I will do better with Synthroid than with levo?

My endo felt my thyroid gland as I was drinking water. He said that my thyroid felt a little irregular but that that was common for hypothyroid people. He ordered an ultrasound but said that getting the ultrasound was not urgent.

Did you tell the Endo about still having hypo symptoms? The , TSH isn't the best way to moniter thyroid disease. It can fluctuate throughout the day. It's much better to go by the free' some of Gimel's posts.You may be one of those that needs to have free's in upper range to feel better, As far as Synthroid goes, what was the Endo's reason for you switching to that? Did he do blood work? If your insurance will cover the Synthroid, it won't hurt to try...but, that doesn't mean it will work better if you have hashi's. What are your symptoms? Why didn't the Endo do an ultrasound in the office? I'm not sure i would be happy with this doc, especially since he believes TSH is the most important thing to look at, and with hashi's( if you have that ) TSH can be even more unstable. I don't think the use of cold medication,or vitamins taken well after the Levo is relavent.
With your TPOab negative, you may not have Hashi's, but you don't list TGab, which can also be positive for Hashi, so without that test, you still don't know.  

I agree with Thelma -- I wouldn't like this doctor.  TSH is more likely to vary throughout the day than the FT4 is.  TSH is a pituitary hormone, so it tells only what the pituitary "thinks" should be happening; as many will attest to on here - the pituitary can go whacko and make mistakes................You need to go by the FT4 and FT3.  

I would agree that an ultra sound may not be "urgent"; however, I do think it's necessary to see what's actually there.  My doctor could not feel anything on my thyroid, but ordered an ultra sound just in case there was something he couldn't feel -- that's how I found out I have nodules.......

I truly urge you to think about finding a different endo.  This one is most likely going to keep you sick for a long time to come.  
Well, the endo is *considering* switching me to Synthroid. His reason, I believe, is that my symptoms have come back and, therefore, the levo must not be doing the job.

What are my symptoms? Soreness and pain in my hands, knees. Sensitivity to cold. Some trouble swallowing. Overall feeling of sluggishness. Lack of the "get up and go" attitude", if you know what I mean.

I was meeting with the endo for the first time. During the visit, I told the endo my recent medical history. He felt my thyroid as I was drinking water, and he performed other examinations. All of that took most of the hour that was reserved for me. Also, this clinic has a special area for ultrasound, and a separate appointment has to be made for that area.

As for the Centrum, I would take the Centrum at 3 AM with my dinner, about 8 or 9 hours before taking levo the next morning.
Your symptoms are certainly hypo! If you switch to Synthroid ask for a bit of a higher dosage at the same time. It may only take 12.5mcg increase...but it looks to me like you could use it..I've been on generic T4 with many dosage increases, and still I'm hypo, i have hashi' need to know if you have the antibodies! If it was me in your situation I would probably just get an increase in dosage, see if that takes care of those symptoms.whether Synthroid or generic, I'd still up the dosage a little :)
                                                                                      Take Care, Thelma
Symptoms coming back doesn't necessarily mean that the levo is not working; it could just mean that you need a higher dose, like Thelma said.  

This is another thing that leads me to believe that you might have Hashimoto's. With Hashi's, the antibodies slowly kill off your thyroid, so eventually, it will stop producing any hormone at all.  As this process takes place, your thyroid will produce less and less on it's own and as that happens, you will  have to replace it with higher doses of med in order to alleviate your symptoms.

I think you should ask your doctor for the TGab test also.

Your FT's are both low enough in their ranges, to warrant an increase in med.  You want to go up slowly, so you can increase by the 12.5 as Thelma suggested or you can try going up even less by alternating dosages.  

At one point, I was on 75 mcg, and needed to go up, but didn't want to go all the way to 88 in one jump, so I alternated 75 one day, 88 the next, which actually gave me 81.5/day.  When I was ready for my next increase, I went on to 88 daily.  Now, I think I'm getting close to being ready for another, so I will try alternating 88 with 100.  There is really no end to the combinations you can come up with by splitting pills, alternating, etc in order to get the dosage you need.

Of course, there is nothing wrong with changing to synthroid; some doctors refuse to write a script for anything else.  Whichever med you decide on, I do think you need a higher dose.
Around 5/18/10, I had a blood test (4 weeks after the last blood test), and the results are in.

TSH = 0.636 (down from 1.016), Free T4 = 1.13 (up from 1.10), Free T3 = 3.4 (down from 3.5)

Also, the doctor said that tests were run for both TG and TPO antibodies. According to the doctor, "the TG was negative (undetectable), and the TPO antibody was 67 International unit/ml (normal <35)". This result, according to the doctor, is "suggestive of autoimmune hypothyroidism".

Now, I was first diagnosed with hypothyroidism in July 2009. My TSH was 147.3. Five days later, I had another blood test, and my TSH was 122.494, and my Free T4 was 0.16, and my ANTI-TPO IGG was 3.0 IU/ml, which was considered negative.  

So, if the ANTI-TPO IGG test that I had in July 2009 is the same TPO test that I had around May 18, 2010, then how is it possible that the July 2009 result was 3.0 and that the May 2010 result is 67? Shouldn't the July 2009 result also have been high?

The doctor says that I can stay with levo or switch to Synthroid, and that I should stay with 137 mcg whether I take levo or Synthroid.

So, is my thyroid's ability to produce the proper thyroid hormones  getting worse? Should I stay with levo, or switch to Synthroid? Should I get a dosage higher than 137 mcg, whichever medication I take? If I switch to Synthroid, is it a good idea to stay with 137 mcg at first and THEN switch to a higher dose?

Also, I had a test for vitamin D, and the result was
VIT D, 25-HYDROXY = 26 ng/ml (normal range = 32 - 100 ng/ml). The doctor recommends that I take 2000 International Units of vitamin D daily. The doctor recommends an over-the-counter drug called cholecalciferol. Does this drug interfere with levo or Synthroid?


What are the ranges for the FT3 and FT4?  These will need to come from your own report, since they are lab specific. Where you fall within the range, along with your symptoms, will determine whether or not you need a dosage increase.  

The fact that your TPOab is 67, means you have Hashimoto's.  Things can change quickly with thyroid issues, so the fact that you TPOab was negative in July '09, but now positive, is not cause for concern.  My thyroid was tested in late 2007 and results fell in "normal" range; by early 2008, my TSH was up to 55+ and my FT4 was below range.  

As the antibodies continue to "kill off" your thyroid, it's possible that you need higher doses of med.  Once your thyroid is completely "dead", meaning it no longer produces hormone, you will be totally dependent on the med.  

Your question about switching to synthroid is a personal decision.  Some do better on synthroid, others do fine on generic - I personally, did not do well at all on synthroid, but do nicely on generic.  Each manufacturer uses different fillers, etc and some people can't tolerate certain ones.  If you think there is an issue with the generic med, you can try synthroid and see if it makes a difference.  

Please post the reference ranges for your FT4 and FT3.

I'm sorry, Barb. I posted these ranges in my first post, and I didn't want to repeat myself and be irritating. :)

Here are the normal ranges for my blood tests:

TSH normal range = 0.35 - 5.5

Free T4 normal range = 0.71 - 1.81

Free T3 normal range = 2.3 - 4.2

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