Hi, I have a TSH, FT3, FT4, and Vitamin D test coming up. Due to my schedule, it is difficult to get to the lab before 10am. I am on NDT and always have suppressed TSH. My endo is aware that my TSH is suppressed, the .01 TSH result I usually get is not an issue.
If I split my NDT dose the day before, 1/2 at 7am and the other 1/2 at midnight (10 hours before the test), will I get accurate results for FT3 and FT4?
Also, are there any recommendation as to how long to avoid taking Vitamin D prior to getting the Vitamin D labs?
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Xheila
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If I split my NDT dose the day before, 1/2 at 7am and the other 1/2 at midnight (10 hours before the test), will I get accurate results for FT3 and FT4?
That's fine, the day before it's suggested to split dose and take last part of dose 8-12 hours before test.
You can continue taking Vit D up to and including the day before the test, on the day of the test take it after the blood draw.
With NDT you dose to the relief of symptom and not a blood test result.
If you are well on your current dose that is the right dose for you and a blood test is just a gauge and a snapshot in time.
Providing you maintain the same regime for all your endo appointments the results should be consistent with any dose increase you may have.
T3 is the most important of all the results and this should be proportionately high in the range than T4 - but just remember that these ranges were introduced to be used with Big Pharmas launch of synthetic T3 Liothyronine and T4 Levothyroxine, and not NDT.
Pennyannie, thanks for your response. I had finally gotten well on my NDT in 2020, with FT3 just over range and FT4 low in range. But I've been feeling pretty horrible for the past month. The symptoms I have are not my customary hypo symptoms I had for 7 years (insomnia, anxiety, and anorexia) but they are the "regular" hypo symptoms (sleeping too much, fatigue) so I'm testing mainly because I'm curious to know if I might be undermedicated or if it is some other health issue. I'm on the same dose of Armour so I want to check if I'm at the same levels as last time. I've been duped before, as my last two medications (NatureThroid and WP Thyroid) were both recalled due to sub-potency. I'm glad you pointed out that the ranges are not necessarily in accordance with NDT treatment!
Yes - I've read about these issues with some NDT brands in the States.
I just a quick look back and see you have been diagnosed with Hashimoto's AI thyroid disease.
It might be an idea to look into the research and suggestion of Dr Izabella Wentz who has this disease and it's very important to heal ones gut in order to get maximum absorption from any thyroid hormone replacement. It's suggested that you look at excluding certain foods, such as gluten, dairy, wheat and get checked out for celiac disease, another AI disease.
You may have already done all this, and I'm sorry if I'm sounding like I'm teaching you to suck eggs :
The symptoms you describe above of insomnia, anxiety and anorexia do not sound like typical hypo to me but rather hyperthyroid symptoms and wonder if you were on slightly too much thyroid hormone replacement.
These symptoms could also be down to Hashimoto's AI disease, as you likely experienced " swings " going from hypo to hyper, and then when the swing inevitably swings back you are left more exhausted and more hypothyroid than before and needing a dose increase.
As your thyroid gland becomes more disabled from these " swings " you will, eventually be left with a totally disabled thyroid gland, with little if any production and need full spectrum thyroid hormone replacement which you are already on, but possible need to fine tune your dose.
So, with Hashimoto's you do have a rocky road to manage - swinging between hyper and hypo symptoms, your own erratic thyroid hormone production and finding the right dose of thyroid hormone at any one time a challenge.
I read sensing a " swing " coming on some people stop their medication for a few days so to try and offset the severity of the attack - does this make any sense - ??
No thyroid hormone replacement works well until your core strength vitamins and minerals are maintained at optimal levels and would suggest you also look at getting your ferritin, folate, B12 and vitamin D tested as we need these all at optimal levels to assist in the conversion in our bodies of the NDT.
Sorry, I've gone on a bit, and you can find more information about everything thyroid on the Thyroid UK website who are the charity who support this forum.
And to answer your question, yes, the blood tests and ranges were all introduced to be used with Big Pharmas T3 and T4 launch in the mid 1950's to compete for market share with the existing medication, Natural Desiccated Thyroid .
With NDT you dose to relieve symptoms and not to fit into a box of numbers - it is that simply if you want it to be though with active Hashimoto's this does throw a big spanner in the works as your own thyroid production is likely erratic.
My T3 runs slightly over " the range" with my T4 at around 25 % and my TSH stuck at 0.01 : this is at 12 hours from dose to blood draw and I take all my dose at around 3 in the morning : I am in no way with any hyper symptoms and If anything I run myself slightly hypo :
P.S. I'm with Graves and post RAI thyroid ablation in 2005 and self medicating with NDT ;
I appreciate your helpful response. And sorry for my slow reply, I've just been too tired to do anything today. My debilitating insomnia was always my main hypo symptom, especially before I was treated for Hashi's. I never managed more than 2 consecutive hours of sleep for 5+ years. The insomnia got better as I increased my level of FT3. Once I hit 50% of the range, I could actually sleep 4-5 hours/night and my doctors decided that was "good enough." It was not. I did not start sleeping a full night until I was at 80% of the range in FT3.
Now, for the past month, I have been sleeping 11 or more hours each day, with just no energy. Exercising makes me worse because I am just beat for the rest of the day if I exert myself. This is unheard of for me, and frankly it is very scary. I've been keeping a sleep diary the past 2 weeks because it is so abnormal of me.
One doctor I had a few years back said that a period of hypersomnia is to be expected after an extended bout of insomnia. I *hope* that is what's going on.
I had a celiac's test (negative) and did try a strict gluten free diet for a year regardless. All I noticed is that I was very hungry, all the time. But this was back when I was really very sick and had a hard time eating enough. What I have noticed is that for a few years, I was not able to tolerate coconut milk, but now that I'm feeling better, I no longer have any issue with coconut milk. Bring on the Thai curry, please!
No worries - there isn't a stop watch on you here, and replying when you feel able, is ok with forum members as we have all been where you are in some shape or form, so understand.
I think " bringing up baby " all alone can't have been much fun and exhaustion at that point in a time a " given " - as your own body clock has been put on hold and then add in living with Hashimoto's and the hyper and hypo " swings " - I'm not surprised you are feeling as you do.
Ultimately it reads as though it has to be all about getting a good high level of T3 for you to be able to function :
Exercise will deplete your T3 level quicker than walking.
Your T3 is needed throughout your whole body to enable you to function and if in short supply symptoms of hypothyroidism will creep back into your daily life.
It might be a good idea to get your ferritin, folate, B12 and vitamin D checked out as these really do need to be maintained at optimal levels to keep your core strength strong and solid.
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