Byronrules 101

[Byronrules101]

Hi I’ve been taking thyroxine for 27 years, over the last few years I have been reduced from 150 mcg down to 75 mcg , my latest test show my TSH 0.05 and my T4 19.0 they don’t test T3 . Does that sound normal , I’m always tired ?

[SeasideSusie Remembering]

Byronrules101

We need reference ranges please. These will be on a print out of your results which you can obtain from the receptionist at your surgery (don't ask the GP, just ask the receptionist and don't accept verbal or hand written results, it needs to be a print out so that no mistakes can be made).

TSH we know is below range which often happens when on thyroid hormone replacement.

FT4 ranges vary so much - 7-17, 9-19, 11-23, 12-22, and others. So we can't interpret your FT4 result.

FT3 is needed as this is the most important test. T3 is the active hormone which every cell in our bodies need. Low T3 causes symptoms. You can have a high FT4 and low FT3 and be symptomatic, this is because your conversion of T4 to T3 is poor.

We also need optimal nutrient levels for thyroid hormone to work well, so we need to test:

Vit D

B12

Folate

Ferritin

If you can't get all tests done with your GP (which is very likely the case) then you might want to consider doing a full thyroid/vitamin panel with one of our recommended labs. Please ask for details if you would like to do this.

[SlowDragon Administrator]

Do you always get same brand of levothyroxine?

Which brand?

For full Thyroid evaluation you need TSH, FT4 and FT3 plus both TPO and TG thyroid antibodies tested. Also EXTREMELY important to test vitamin D, folate, ferritin and B12

Low vitamin levels are extremely common, especially if you have autoimmune thyroid disease (Hashimoto's) diagnosed by raised Thyroid antibodies

Low vitamin levels are extremely common if under medicated

Low vitamin levels tend to lower TSH too

Ask GP to test vitamin levels

Recommended on here that all thyroid blood tests should ideally be done as early as possible in morning and before eating or drinking anything other than water .

Last dose of Levothyroxine 24 hours prior to blood test. (taking delayed dose immediately after blood draw).

This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip)

Is this how you do your tests?

Private tests are available as NHS currently rarely tests Ft3 or thyroid antibodies or all relevant vitamins

List of private testing options

thyroiduk.org/getting-a-dia...

Medichecks Thyroid plus vitamins including folate (private blood draw required)

medichecks.com/products/thy...

Thriva Thyroid plus antibodies and vitamins By DIY fingerpick test

thriva.co/tests/thyroid-test

Thriva also offer just vitamin testing

Blue Horizon Thyroid Premium Gold includes antibodies, cortisol and vitamins by DIY fingerprick test

bluehorizonbloodtests.co.uk...

If you can get GP to test vitamins and antibodies then cheapest option for just TSH, FT4 and FT3

£29 (via NHS private service ) and 10% off if go on thyroid uk for code

thyroiduk.org/getting-a-dia...

monitormyhealth.org.uk/thyr...

There’s currently an incorrect obsession by many GP’s to keep reducing levothyroxine to bring TSH up into range (usually minimum of 0.5) ...actually all that frequently happens is TSH drops even lower along with vitamin levels and patients quality of life nose dives

guidelines on dose levothyroxine by weight

Even if we don’t start on full replacement dose, most people need to increase levothyroxine dose slowly upwards in 25mcg steps (retesting 6-8 weeks after each increase) until on full replacement dose

NICE guidelines on full replacement dose

nice.org.uk/guidance/ng145/...

1.3.6

Consider starting levothyroxine at a dosage of 1.6 micrograms per kilogram of body weight per day (rounded to the nearest 25 micrograms) for adults under 65 with primary hypothyroidism and no history of cardiovascular disease.

gp-update.co.uk/Latest-Upda...

Traditionally we have tended to start patients on a low dose of levothyroxine and titrate it up over a period of months.

RCT evidence suggests that for the majority of patients this is not necessary and may waste resources.

For patients aged >60y or with ischaemic heart disease, start levothyroxine at 25–50μg daily and titrate up every 3 to 6 weeks as tolerated.

For ALL other patients start at full replacement dose. For most this will equate to 1.6 μg/kg/day (approximately 100μg for a 60kg woman and 125μg for a 75kg man).

If you are starting treatment for subclinical hypothyroidism, this article advises starting at a dose close to the full treatment dose on the basis that it is difficult to assess symptom response unless a therapeutic dose has been trialled.

A small Dutch double-blind cross-over study (ArchIntMed 2010;170:1996) demonstrated that night time rather than morning dosing improved TSH suppression and free T4 measurements, but made no difference to subjective wellbeing. It is reasonable to take levothyroxine at night rather than in the morning, especially for individuals who do not eat late at night.

BMJ also clear on dose required

bmj.com/content/368/bmj.m41

bestpractice.bmj.com/topics...