When using NDT to treat low thyroid hormone levels, how would you know if you are overmedicated?
I have read so much information, saying different things. Not sure what is correct.
Some say look at lab results - stay within the top part of the range, but don't go over. Some say lab results are not relevant because they were developed for synthetic T4 use, not NDT.
Some say to go by how you feel - if your symptoms are alleviated, you are good, even if your numbers are over range. They say you will know you are overmedicated if you start to feel anxious, on-edge, can't sleep, heart palpitations, etc.
Can anyone shed some light on this, please?
Thank you very much for your help!
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Overlooked
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I would say it was a combination of the two: symptoms backed up by blood tests. Because the problem is, so many symptoms can be due to both over and under-medication. So, for example, if you feel anxious, but your FT3 is only 45% through the range, you are hardly likely to be over-medicated, most likely under-medicated.
Trembling hands is a good indication because I don't think you ever get that with under-medication. And, I know that for me, it's a sure sign of over-medication whether on NDT, Levo or whatever. But not everybody gets that.
One thing is certain, though, it has nothing to do with the TSH! Doctors are inclined to tell you you're over-medicated if your TSH is below-range, whatever the levels of your Frees, because they don't know any better. But we know that when taking T3 your TSH is going to be low, and it's the FT3 that is the best indicator of thyroid status.
Thank you for your reply, and your advice. I agree about the TSH not being the right indicator of thyroid health!
So, if you feel well, and have no adverse symptoms, but your numbers are over range, would you go by how you feel? Does that trump numbers that are over range?
Well, depends how far over-range. But you have to remember that ranges are only rough guides of what levels the majority of people have, not rigid boundaries that you mustn't cross. Some people just need their levels higher than others, that's all.
It might interest you to read this article about ranges:
Thank you very much. I just read through the article. The basic message in the article is actually what I have had to argue (as in, firmly state my case) with my doctor, trying to get him to acknowledge that a value just inside the upper level of the TSH reference range isn't significantly different from a value just outside that same upper level - the two values are right next to each other, but one is usually viewed as 'normal', and the other is deemed 'abnormal', which makes no sense to me.
My current FT3 and FT4 values are a tad over the upper reference range. My doctor has immediately told me to decrease my dose, fearing that I will get heart problems, etc.
I had expected that if I was overmedicated, I would experience all the things that people often talk about - anxiety, sleeplessness, heart palpitations, feeling on edge.... I haven't had any of these symptoms while on NDT. I actually feel the best I have felt in years (since dose was increased recently).
I am thankful that at least my doctor was willing to let me try some thyroid treatment (nobody else previously would acknowledge I had any problem with my thyroid levels), but I wonder if maybe my levels might be ok just over range, rather than back down within the range? I really don't want to go back to the miserable existence I was living before the increased NDT.
Appreciate very much your advice and help. Thank you!
Doctors know nothing about reference ranges nor how to interpret blood test results. Everything is black and white for them, they cannot envisage anything in between. Maybe sent your doctor a copy of that article?
Perhaps don’t adjust anything for a little while to see if your frees rise any more. It would very much depend on how long you’ve been on your current dose because your body could still be within the throes of adjusting to it, meaning your frees could still rise
If you’re concerned about your frees being over range you could try at some point to tentatively reducing your dose by a very small amount to see if that gets you back to upper limits and to test what that feels like. If you still feel well, then voila!
I take Metavive, a glandular with the same principal as NDT. I reduce or increase according to how I feel mainly but try to stay just under the uppermost range in order to keep my GP happy
A little while ago FT3 was way over and I could feel it. Sleeplessness, anxiety, sweats, irritable. In my case it took a while for my body to register that I was slightly over range because it then allowed me to get well over before alerting me
When I am over medicated my tongue swells and my speech is affected, exactly as when I am under medicated. A doctor friend told me that is a classic sign of untreated hypothyroidism. Regarding increased anxiety if I feel I am over medicated I test my T4 and T3 levels.
Overlooked, I continue to be disabled with my thyroid illness, for over ten years, so have tried a great variety of different doses, including very high ones. When I was on extremely high doses of NDT (8 grains or more) I didn't have any general symptoms of over medication. After several years on doses like that, I started to experience atrial fibrillation, which I took to mean that I was overmedicated, so I have cut down to a much more usual dose.
I had been expecting to experience some kind of classic over medication symptom, something in the realm of being speeded up, shaky, hot in temperature, etc, but I kept a very close eye on symptoms, including pulse and blood pressure, and there was nothing I could detect. Perhaps a few tiny tiny things, like a day of higher pulse when starting a new dose, or a few episodes when my heart felt strange. But those were just single isolated incidents, when I already had pretty extreme symptoms of not being medicated.
It is possible that whatever is stopping the thyroid hormone from getting into my cells properly also stopped me from feeling overmedication symptoms, so I might be a bit unusual in this.
I would definitely say that symptoms are more important than blood test results in a case like yours.
And I definitely agree with you that the ranges to some extent are arbitrary. The numbers directly under the range and over the range are very close to each other... Saying one is over and the other is under is a line someone has drawn in the sand. These ranges were originally developed by testing a lot of people and then setting up the range that *most people* are inside. I don't have the figures in front of me, but 'most people' will have been 90% of the population or some similar number, so there would always have been some group of people who fall outside the range.
For testing freeT3 in particular, the half life of the medicine is so short, that in some ways the blood test is just a function of how long you have waited after taking a dose to do a blood draw. Which applies a little bit to the other numbers which vary throughout the day, too.
But anyway, conclusion is, that if you feel much better on a dose that is a little bit outside the range there is nothing to worry about. Symptoms are much more important than blood tests, as symptoms are something that we always know is a true indicator of how well you are (the whole goal of treatment is to reduce symptoms), while blood tests are always a snapshot of an abstraction viewed through a filter. Blood tests can be seen as a guide to help us get there, but a reduction in symptoms is the Real Thing we are hoping to find.
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How do you know if you're overmedicated?
TSH and FT4 levels on NDT?
Treating the lab results- NOT the patient 
Despite the lab results, I don't feel overmedicated
