I have had a total Thyroidectomy for Follicular cancer and was started on 125mg Levothyroxine and that was reduced to 100mg after a few months. I had read on the web about the timing of the six monthly blood test at the Hospital, I asked on Health Unlocked about this and it was confirmed that the best time for a Thyroid blood test was 9am in the morning before I take my Levothyroxine, which I usually take at 7.30am. My blood tests for TSH over the last two years have been between 1.7 and 0.53 which was the latest one. My Thyroid Nurse at the cancer clinic says the plan is to keep the reading under 2, she also said that it does not matter what time I have the blood test as it takes 7 months to show any difference anyway. I have had no changes in Levothyroxine other than the initial change down to 100mg two ears ago. So I am now a bit confused. Can you help please?
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AnnieJo41
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It’s true the TSH is an extremely unreliable measure. Not 7 months out unreliable but certainly weeks.
Most argue it shouldn’t be the focus of medics attention & should never be the only measure taken. FT4 & FT4 is far more important were they tested?
TSH can takes about 6 - 8 weeks to respond, which is why we recommend tests are repeated after at least 6 weeks of a consistent dose.
Drs / nurses looks for in range levels & don’t account for variations. It is better for us if the testing is consistent & if the test is shown at time when TSH is likely to be high & Frees low in range it might be difference between being in or out of range.
Hi, Yes I have been feeling very tired recently, but I do have other illnesses, namely Insulin dependant diabetes and I am over 80years old but usually feel fairly energetic. Over the two years I have been tested (every 6months) I have had my blood tested at all different times of the day but now I see the sense in sticking to one time of day and before taking Levothyroxine. Thanks for replying. Annie.
Hi AnnieJo , if you read the early replies to this post ( replies 3, 4 ,5, 6 ) you will find multiple research papers showing why thyroid testing is best done 24 hrs from last dose Levo / early am test / without eating breakfast . healthunlocked.com/thyroidu.... list-of-references-
Ask the nurse for her evidence of why she thinks these things make no difference to test results .... (she won't be able to produce any )
time of last dose does not affect TSH level on that day, this is true ..... but it will affect fT4 level and this matters if fT4 is being tested ( and it should be, if they want to have even the remotest idea what is going on).
the time of day the test is taken will affect the TSH result .
as does eating breakfast.
The difference may be small, but small differences can be significant when trying to optimise thyroid hormone levels / dose .
Hi, Yes I am convinced now that sticking to an early morning blood test will produce more consistent results after reading all the evidence. I haveType 3 Diabetes caused by a Total Pancreatectomy 12 years ago so not eating before the blood test might be a bit of a problem but I will take some glucose tablets just in case I go Hypo. I will also ask the Nurse about my fT4 level and why she thinks consistency with the timing of my blood test wouldn’t make a difference. Thanks for your help. Annie
the 'not eating' bit is not essential , if doing so would cause you problems.
it's just one part of the toolkit for getting results that are consistent and therefore comparable .
you could for example choose to stick to the same drink / breakfast routine for every blood test ... ie always a cup of tea and toast , or whatever......
you just need to be aware that if you've eaten breakfast , the TSH result may be a bit lower than if you hadn't.
Thanks for replying. I was started on Accord Levothyroxine and I have tried to stick with these, the Chemist sometimes sends me Teva but I have heard these can cause upsets so I reject them. I am going to get my Doctor to name the brand Accord on my repeat prescription now. I take the Better You sprays because 12 years ago I had a Total Pancreatectomy which made me a Type 3 insulin dependant Diabetic, because of this I have no digestive enzymes (I take Creon) and I find it difficult to absorb Vitamins supplements in tablet form and the sprays are absorbed in the cheek and mouth I understand. The spays I take are Multivitamin Vitamins A, D, C, K, B complex, VitB12 and also I take Iron and Turmeric also calcium Calcichew ( these are prescribed by my Doctor). I have only been on the sprays about two weeks. I had Vitamin D and Ferritin tested three months ago the Vit D was 85 and the Ferritin was 12. That’s why I started on the Iron spray which I have only recently found it in spray form and I knew that 12 was low, it has been between 12 and 14 for the last 12 years since my operation. I will get them all tested again as you suggest.
Recommended that all thyroid blood tests early morning, ideally just before 9am, only drink water between waking and test and last dose levothyroxine 24 hours before test
This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip)
Private tests are available as NHS currently rarely tests Ft3 or all relevant vitamins
If you normally take levothyroxine at bedtime/in night ...adjust timings as follows prior to blood test
If testing Monday morning, delay Saturday evening dose levothyroxine until Sunday morning. Delay Sunday evening dose levothyroxine until after blood test on Monday morning. Take Monday evening dose levothyroxine as per normal
Monitor My Health (NHS private test service) offer thyroid and vitamin testing, plus cholesterol and HBA1C for £65
IMPORTANT......If you are taking vitamin B complex, or any supplements containing biotin, remember to stop these 5-7 days before ALL BLOOD TESTS , as biotin can falsely affect test results
In week before blood test, when you stop vitamin B complex, you might want to consider taking a separate folate supplement (eg Jarrow methyl folate 400mcg) and continue separate B12
Firstly, no offence but most British doctors and nurses know very little about how to manage this condition. They get negligible training on something that's complex. And thyroid doctors are actually Diabetes specialists. Never have your blood tested later. Thyroid function varies throughout the day and even though you have no thyroid, ditto, I found it rises. I did a 24 hour test at the hospital where they took it every 2 hours or so, and it rose, even without levo meds on the day - just based on what I'd taken on the previous days. On synthetic meds. So no don't change it about. You'll get a false high.
Thanks for replying. Yes, I have been feeling so tired. I do have other conditions as well i.e. Type 3 Diabetes caused by having a total Pancreatectomy 12 years ago and I am over 80 years old but I don’t usually feel so tired. I am going to have my blood taken at 9am in a weeks time and see what that shows. I will try to fast but it is a bit more difficult when you have Diabetes because of blood sugar going low but I will have to maybe have glucose tablets. Last time the blood results for TSH were 0.53. Thanks again. Annie
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Hypothyroidism
Sorry another query on test results
Confused, could you help me understand please?
confused 
Confused Newbie
