Had my annual review of medication today. I take 75mcg Levothyroxine and 10mcg of Liothyronine.
Results are back:
tsh 0.52 [0.27-4.2]
ft4 12 [11-22]
T3 not tested as apparently only done if tsh not in range 🙄
Would the t3 I take be suppressing my ft4? Hence such a low value? I feel quite rotten, cold intolerance, rapid weight gain etc but I know my GP won’t up my Levo if I ask as ‘in range’. Should I be concerned or is it a case of not needing a high T4 result if taking t3, similar to expecting tsh to be suppressed when supplementing with medication.
Hope that all makes sense, thanks in advance!
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Confused22
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Sorry, realised I forgot to specify - I fasted for 12 hours before the test, as I always do. Test taken at 8:30am. Last Liothyronine taken 12 hours before test and last Levothyroxine taken 36 hours before test. Thanks!
Well, that's one of the reasons your FT4 is so low (I wouldn't call it 'suppressed'): 36 hours is too long. It should only be 24 hours. But, yes, taking T3 does lower the FT4. For some people that matters, for others it doesn't. But you can't know if it's the low FT4 causing your symptoms without getting the FT3 tested. Could be that is too low. The NHS still hasn't understood the importance of the FT3 level, they make all sorts of excuses for not testing but it still comes down to ignorance, so most people get it tested privately. Because it really is the most important number.
Thank you, that makes sense then. Yes I was amazed - I called prior to the test and explained as I was taking t3 can they test that as well and was told by the gp that they couldn’t request it (despite they themselves prescribing it for me) and it was at the discretion of the lab. Looks like a private test is needed then. GPS have definitely tested t3 before so it’s incredibly frustrating they didn’t bother this time! Thank you for your time in responding
Yes, it seems incredible that a lab technician can over-rule a doctor where lab tests are concerned. But that's the state of things at the present time. Oh, well, that's one way to reduce the population, I guess!
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
last dose levothyroxine was too long before test at 36 hours so is falsely low …..however it is very low
You likely have room to increase
Request or experiment with increasing to 87.5mcg daily
Then retest correctly 8 weeks later
Which brand Levo are you taking
What vitamin supplements are you taking
When were vitamin D, folate, ferritin and B12 last tested
That’s so helpful, thank you and makes good sense. I appreciate you explaining it for me. Looks like as t3 wasn’t tested I’ll need a private test doing now anyway, so I shall be better prepared with the levo dosing for that thanks to your help and can take things from there.
I take Teva Levo as lactose free. No other supplements. I haven’t had vit D, folate, ferritin or B12 tested for 18 months. GPs won’t test unless a medical need. I didn’t appreciate they made such a difference to my absorption - do you have any links you wouldn’t mind sharing to point me in the right direction to learn more about those points please?
Thank you. Yes I wasn’t surprised at the tsh level (to be honest 18 months ago it was wayyyyyy lower - almost undetectable). I’m so annoyed the GP (who is the one prescribing my T3!) left it up to the lab to decide whether or not to test. Now they haven’t yesterday’s blood test really seems a waste of time and I’ll have to go down the private route.
Can you share why vitamin levels are so important to be tested as well please? Many thanks for your help
Vitamin D deficiency is frequent in Hashimoto's thyroiditis and treatment of patients with this condition with Vitamin D may slow down the course of development of hypothyroidism and also decrease cardiovascular risks in these patients. Vitamin D measurement and replacement may be critical in these patients.
Vitamin D insufficiency was associated with AITD and HT, especially overt hypothyroidism. Low serum vitamin D levels were independently associated with high serum TSH levels.
The thyroid hormone status would play a role in the maintenance of vitamin D sufficiency, and its immunomodulatory role would influence the presence of autoimmune thyroid disease. The positive correlation between free T4 and vitamin D concentrations suggests that adequate levothyroxine replacement in HT would be an essential factor in maintaining vitamin D at sufficient levels.
Our results indicated that patients with hypothyroidism suffered from hypovitaminosis D with hypocalcaemia that is significantly associated with the degree and severity of the hypothyroidism. That encourages the advisability of vit D supplementation and recommends the screening for Vitamin D deficiency and serum calcium levels for all hypothyroid patients.
Same applies to low B12 - extremely common in hypothyroid patients
All patients who are hypothyroid should have B12 tested
There is a high (approx 40%) prevalence of B12 deficiency in hypothyroid patients. Traditional symptoms are not a good guide to determining presence of B12 deficiency. Screening for vitamin B12 levels should be undertaken in all hypothyroid patients, irrespective of their thyroid antibody status. Replacement of B12 leads to improvement in symptoms
Patients with AITD have a high prevalence of B12 deficiency and particularly of pernicious anemia. The evaluation of B12 deficiency can be simplified by measuring fasting serum gastrin and, if elevated, referring the patient for gastroscopy.
Levothyroxine can decrease serum homocysteine level partly; still its combination with folic acid empowers the effect. Combination therapy declines serum homocysteine level more successfully.
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