I had my thyroid checked early December and my TSH was Serum TSH level 0.20 mu/L [0.35 - 4.7]; my Serum free T4 level was 18 pmol/L [7.8 - 21.0]. I have Hashimotos and my Thyroid specialist reduced my Levothyroxine from 100 everyday to 100 for 5 days and 75 for 2 days. I have just been retested and seem a little confused as my TSH has risen but also my Free T4 see results: 21/4/23 Serum TSH level 4.6 mu/L [0.35 - 4.7]; Serum free T4 level 23 pmol/L [7.8 - 21.0]; Above high reference limit. This seems a little strange to me and not something I'm used to, to have increased TSH as well as above reference limit of Serum Free T4.
Could someone please give me some advice as to what this means, if anything I was expecting a slightly higher say 2.0 TSH and a slightly lower Serum Free T4. I have been hungrier and also had a lot of energy though.?
Written by
Sewit1
To view profiles and participate in discussions please or .
Not very common but could be assay interference with the TSH. You really need TSH, fT4 and fT3 measured to know where you stand. It could also be erratic secretion of T3 due to autoimmune activity, so again they need to measure fT3.
Thank you I think it may be interference with TSH. My doctors won't test FT3 usually but maybe as I have an abnormal reading they will override their usual decision. My test result says I need to see a practice nurse so will book in, maybe ask for a re-test also
GPs can't usually get fT3 tested which is stupid as the test costs about £1. You could suggest your doctor speaks to the biochemist / clinical scientist to get advice about the unusual results. This might get the fT3 done.
There is quite an art to testing so that we get consistent and accurate results.
Did you do the test as per the protocol recommended here? Recommended blood test protocol: Test at 9am (or as close as possible as TSH is highest then), fasting, last levo dose 24hrs before the blood draw & no biotin containing supplements for 3-7 days (Biotin can interfere with thyroid blood results as it is used in the testing process)?
Testing like this gives consistency in your results and will show stable blood levels of hormone. Taking Levo just prior to blood draw can show a falsely elevated result and your GP/Endo might change your dose incorrectly as a result.
For a proper assessment of your thyroid function you need 3 tests - TSH, FT4 & FT3. Private tests are available, see link for companies offering private blood tests & discount codes, some offer a blood draw service at an extra cost. thyroiduk.org/help-and-supp...
Do you always get the same brand of Levo at every prescription? Many find brands are not interchangeable.
What were your most recent results for ferritin, folate, B12 & D3?
Many with autoimmune thyroid disease aka Hashimoto's benefit from a gluten free diet. A smaller percentage of those also need to remove dairy from their diet to feel well. These are intolerances and will not show up on any blood test.
I did the test at 11 am as that was the only appointment available. I will take a private test also as I can never get all of the tests I require at the doctor. My B12 was 330 last done at the doctors, I do supplement. I feel well in myself and no rapid heartbeat so will test again and private test to ensure no false test reading. Thanks for the information reminder.
This B complex has all the right vitamins at a not unreasonable cost for 90 days supply(also contains folate). Once B12 is good you can stop the stand alone B12 and just continue with the B complex. amazon.co.uk/Liposomal-Soft...
What were the timings of your blood tests? When was your last dose of Levo prior to the blood draw? Forum advice is to get the earliest possible time for a thyroid blood test & have only water prior to the test. Also ensure that last Levothyroxine dose is 24 hours before the blood draw
For a more complete picture of your thyroid health I would look to test FT3 in addition to FT4 and TSH.
Most GPS and even some endocrinologists don’t routinely test FT3 and some only test FT4 if TSH is not in range. That’s why so many forum members test privately for TSH, FT3, FT4, thyroid antibodies and key vitamins (ferritin, folate, vitamins D and B12).
Content on HealthUnlocked does not replace the relationship between you and doctors or other healthcare professionals nor the advice you receive from them.
Never delay seeking advice or dialling emergency services because of something that you have read on HealthUnlocked.
What does it mean to have normal TSH and Free T3, but have high free Thyroxine (T4)?
High tsh and high t4 - help!
high free thyroxine and normal tsh.. difficulty to conceive
Is my Tsh too low t3 too high free t4 too high or is endo wrong
High TSH with Low T3 & T4
