Doubling Dose of Thyroxine?

[B12again]

Hi, I’d like your thoughts and opinions (I’ll make the decision 🙂) on doubling my thyroxine dose by taking two tablets per day. I’m on 50mg, been at that for years, but I still feel cold especially feet and hands. My TSH level is 3.28 and whilst it might be in range, I understand it should be more around 1. I intend asking my GP in March (I’m B12 deficient and SI with hydroxocobalamin and will be discussing B12 provision with him then after new NICE guidelines are published) but I’d like to try it sooner if feesible. Your thoughts would be appreciated.

[SlowDragon Administrator]

You need to get FULL thyroid and vitamin testing done ideally BEFORE increasing dose

Request GP test NOW or test privately

Only ever increase by 25mcg per day

Cut a 50mcg tablet in half

Retest again in 6-8 weeks after being on 75mcg daily

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)

Likely to need several further increases in dose over coming months

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

Testing options and includes money off codes for private testing

thyroiduk.org/testing/

Medichecks Thyroid plus antibodies and vitamins

medichecks.com/products/adv...

Blue Horizon Thyroid Premium Gold includes antibodies, cortisol and vitamins

bluehorizonbloodtests.co.uk...

Only do private testing early Monday or Tuesday morning.

Link about thyroid blood tests

thyroiduk.org/testing/thyro...

Link about Hashimoto’s

thyroiduk.org/hypothyroid-b...

Symptoms of hypothyroidism

thyroiduk.org/signs-and-sym...

Tips on how to do DIY finger prick test

support.medichecks.com/hc/e...

Medichecks and BH also offer private blood draw at clinic near you, or private nurse to your own home…..for an extra fee

[SlowDragon Administrator]

Approximately how much do you weigh in kilo

guidelines on dose levothyroxine by weight

Even if we frequently start on only 50mcg, most people need to increase levothyroxine dose slowly upwards in 25mcg steps (retesting 6-8 weeks after each increase) until eventually on, or near full replacement dose

pathlabs.rlbuht.nhs.uk/tft_...

Guiding Treatment with Thyroxine:

In the majority of patients 50-100 μg thyroxine can be used as the starting dose. Alterations in dose are achieved by using 25-50 μg increments and adequacy of the new dose can be confirmed by repeat measurement of TSH after 2-3 months.

The majority of patients will be clinically euthyroid with a ‘normal’ TSH and having thyroxine replacement in the range 75-150 μg/day (1.6ug/Kg on average).

The recommended approach is to titrate thyroxine therapy against the TSH concentration whilst assessing clinical well-being. The target is a serum TSH within the reference range.

……The primary target of thyroxine replacement therapy is to make the patient feel well and to achieve a serum TSH that is within the reference range. The corresponding FT4 will be within or slightly above its reference range.

The minimum period to achieve stable concentrations after a change in dose of thyroxine is two months and thyroid function tests should not normally be requested before this period has elapsed.

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.

Also here

cks.nice.org.uk/topics/hypo...

TSH should be under 2 as an absolute maximum when on levothyroxine

gponline.com/endocrinology-...

Graph showing median TSH in healthy population is 1-1.5

web.archive.org/web/2004060...

Comprehensive list of references for needing LOW TSH on levothyroxine

healthunlocked.com/thyroidu....

onlinelibrary.wiley.com/doi...

If symptoms of hypothyroidism persist despite normalisation of TSH, the dose of levothyroxine can be titrated further to place the TSH in the lower part of the reference range or even slightly below (i.e., TSH: 0.1–2.0 mU/L), but avoiding TSH < 0.1 mU/L. Use of alternate day dosing of different levothyroxine strengths may be needed to achieve this (e.g., 100 mcg for 4 days; 125 mcg for 3 days weekly).

Vitamin levels likely low if been left under medicated on too low dose levothyroxine

[helvella Administrator Thyroid UK]

You just might find this helpful in arguing your TSH level.

This is a link to a very good article in the British Medical Journal discussing what the 'normal range' really is. Very readable.

The normal range: it is not normal and it is not a range

helvella.blogspot.com/p/the...

[DippyDame]

The decision is always yours! But without knowing your current labs I would suggest doubling your levo dose to 100mcg is far too much, too soon...you may miss your sweet spot and probably upset your system. Usual increase in by 25mcg....the body needs time to adjust between increases.

Taking replacement thyroid hormone is not like taking paracetamol for a headache!

50mcg is a starter dose and you should have been tested again after 6/8 weeks and dose increased back then

We need to be on a steady dose for at least 6 weeks before testing.

Your TSH is too high but once medicationis initiated FT4 and FT3 are the most important readings. When adequately medicated TSH should be 1 or under as you say.

thyroidpatients.ca/2021/07/...

In addition to optimising vit B12 it is essential to also do so for Vit D, folate and ferritin.....they support thyroid function/T4 to T3 conversion.

When were you last tested.....TSH, FT4, FT3, vit D, vit B12, folate, ferritin and thyroid antibodies TPO and Tg?

Important to test before increasing.

You could then increase levo by only 25mcg now that would allow time before March for the hormone level to settle. But, your GP may take a dim view of this, so you will need to be prepared to tactfully justify your decision by showing improved symptoms and lab results.

thyroiduk.org/signs-and-sym...

For comparison make a list of relevant symptoms from the above link before you consider increasing your dose.

GP's guidelines confirm that symptoms must be considered during diagnosis....not just the list of labs as often happens.

GP's first question should be, "How do you feel?"!!

It's clear you need the increase...but you also need a full thyroid test before doing so.