Adding T3 to T4, not sure which way to go - Thyroid UK

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Adding T3 to T4, not sure which way to go

Longinthetooth profile image
14 Replies

If I start to take T3 do I reduce my T4 or keep taking the same amount. I'm on just over 100mcg of T4. I've had a good year but all my symptoms have returned., weight gain, weariness, etc. Has anyone else experienced this? I may not require T3 but why have these symptoms returned?

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Longinthetooth profile image
Longinthetooth
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14 Replies
SlowDragon profile image
SlowDragonAdministrator

First step is to get FULL thyroid and vitamin testing

You may just need increase in levothyroxine and/or vitamin levels improving

The aim of Levothyroxine is to increase the dose slowly in 25mcg steps upwards until TSH is under 2 (many patients need TSH significantly under one) and most important is that FT4 is in top third of range and FT3 at least half way through range

NHS guidelines on Levothyroxine including that most patients eventually need somewhere between 100mcg and 200mcg Levothyroxine.

nhs.uk/medicines/levothyrox...

Also note what foods to avoid (eg recommended to avoid calcium rich foods at least four hours from taking Levo)

All four vitamins need to be regularly tested and frequently need supplementing to maintain optimal levels

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

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, best not mentioned to GP or phlebotomist)

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 ultra vitamin (doesn’t include folate)

medichecks.com/products/thy...

Thyroid plus vitamins including folate (private blood draw required)

medichecks.com/products/thy...

Thriva Thyroid plus vitamins

thriva.co/tests/thyroid-test

Blue Horizon Thyroid Premium Gold includes vitamins

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...

Medichecks - JUST vitamin testing including folate - DIY finger prick test

medichecks.com/products/nut...

Medichecks often have special offers, if order on Thursdays

Come back with new post once you get results

Longinthetooth profile image
Longinthetooth in reply to SlowDragon

Thank you. I've had blood tests which are now back. The nurse practitioner phoned me this morning to say that my bloods are ok. I think she said my thyroid is 5.5. Because I said I feel so worn out a doc will phone me this afternoon. I feel as I did pre diagnosis of this under active thyroid. Bloody awful. Don't know which way to turn.

greygoose profile image
greygoose in reply to Longinthetooth

You definitely need an increase in levo. You're still very hypo. You're hypo when your TSH gets to 3! So, if this nurse thinks your bloods are OK, she's extremely ignorant about thyroid.

Besides, TSH is not 'your thyroid'. It is a pituitary hormone. Thyroid Stimulating Hormone, it's the message your pituitary sends to your thyroid to tell it to make more hormone. And, right now, your pituitary is screaming out or more hormone. Not surprised your symptoms have come back. When taking thyroid hormone replacement - like levo - the TSH should come down to 1 or under. The nurse needs to go back to school!

Longinthetooth profile image
Longinthetooth in reply to greygoose

Thanks again. I went up to 150 of levo in Nov/Dec & felt good. My doc said at end of Dec I was on too much, not sure what my bloods said. I had a think about it & I think my heart was racing a bit plus night cramps had started. I cut down to 100 but felt not enough so am now know 112.5 (cut a 50 into 4). Night cramps gone & racing heart. Worried if I go back to 150. Not sure at all.

greygoose profile image
greygoose in reply to Longinthetooth

Well, all I can tell you is that at this moment, you are very hypo, and that's why your symptoms have come back. You need to get hold of your results for the time your doctor reduced your levo. Your TSH was probably suppressed, which causes a knee-jerk reaction in most doctors. But that doesn't tell you what your thyroid hormone levels were. If your doctor is only testing TSH, he doesn't know anything about thyroid, either!

Do you know if you have Hashi's?

Longinthetooth profile image
Longinthetooth in reply to greygoose

Don't know. I will try & order a print of my bloods from reception. My endocrinologist appt earlier this year was cancelled because of covid. Mind you, I never have a great deal of faith in him. I get more advice here every time. Should I ask the doc today if I should go back to 150?

greygoose profile image
greygoose in reply to Longinthetooth

Well, try 125 mcg first.

I can understand why you don't have faith in your endo. They tend not to know much about thyroid.

Longinthetooth profile image
Longinthetooth in reply to greygoose

I will, thanks. As always you guide me in the right direction.

greygoose profile image
greygoose in reply to Longinthetooth

You're welcome. :)

SlowDragon profile image
SlowDragonAdministrator in reply to Longinthetooth

Is this TSH?

Obviously a TSH over 2 is too high for anyone on levothyroxine

So you need 25mcg dose increase in levothyroxine and bloods retested in 6-8 weeks

As been very under medicated it’s likely you also have low vitamins. Ask GP to test vitamin D, folate, ferritin and B12

What vitamin supplements are you currently taking?

Getting FULL testing at next thyroid test ....privately if necessary......Just testing TSH is completely inadequate.

Also ....guidelines on dose of levothyroxine by weight

Even if we don’t start on full replacement dose, most people need to increase 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...

Obviously some people need higher dose....especially if lactose intolerant

Longinthetooth profile image
Longinthetooth in reply to SlowDragon

By the way my body doesn't make TSH as told to me by my endocrinologist. I had a small pituitary tumour removed in 2015.

SlowDragon profile image
SlowDragonAdministrator in reply to Longinthetooth

I think she said my thyroid is 5.5. Because I said I feel so worn out a doc will phone me this afternoon.

Then you better find out what this 5.5 is ....

Because it sounds like TSH. You are legally entitled to copies of your blood test results and ranges

On levothyroxine it’s ALWAYS absolutely essential to test Ft4 and Ft3 .....sadly NHS rarely tests either

Lalatoot profile image
Lalatoot

The symptoms have returned because the dose you are on is no longer sufficient or your body has stopped absorbing it fully or stopped converting it fully.

Why could this be?

Gut problems or taking levo with food or supplements would hamper absorption.

Liver problems or low vitamins could hamper conversion or cause symptoms themselves.

Stress or a major change in lifestyle or diet.

Or with thyroid sometimes there seems to be no one factor.

I would suggest that you think about any changes or events that could have set things of kilter.

Get vitamins D, ferritin, folate and B12 levels checked. These levels need to be in the top half of their ranges to be effective.

Get TSH, FT4 and FT3 tested. This will let you see if an increase in levo is needed in the first instance. It may also show any conversion problems.

Adding T3 is not easy or quick and you then have 2 doses of medication to alter to get optimal. T3 is getting more difficult to source at the moment too so I would always suggest exploring or the levo options first if it has worked for you before.

Longinthetooth profile image
Longinthetooth in reply to Lalatoot

Thank you. I only ever take my levo about 5.30am & then go back to sleep. This site tells everyone about not drinking caffeine, etc with it. Not sure what's wrong. Feel like I'm back to square 1 before I went on levo, same symptoms. Gluten free diet. Whole foods. No processed. Never mind.

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