How can I have hypo symptoms but a fast heart r... - Thyroid UK

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How can I have hypo symptoms but a fast heart rate on NDT?

Boon79 profile image
20 Replies

I'm currently on 2 grains of Thai Thiroyd which I've slowly worked up to (from 100mcg of levothyroxine). My hair has stopped falling out which is great, however I have a fairly fast heart rate at 90bpm resting, but still have hypo symptoms, such as feeling chilly, itchy inner ears, bloating, and a seriously dry mouth. I'm aware that hypothyroidism usually causes a slow heart rate, so whats going on??? I have been on 2 grains for 7 days now, taking 1 at 11pm and 1 at 6am. I'm trying to hold at 2 grains for another 4 weeks until I get private blood tests as per STTM advice.

The levothyroxine I was taking made me feel well but ironically hair loss was the main reason for switching to NDT.

I am taking iron supplements and thyroid support supplement (not containing thyroid tissue) late afternoon.

Surely 2 grains is enough compared with 100mcg of levothyroxine?

Could it be that NDT just isn't for me?

Any advice would be really appreciated!!!

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SlowDragon profile image
SlowDragonAdministrator

High heart rate can suggest over replacement

Have you had blood tested since starting on NDT

A thyroid support supplement sounds highly dubious, probably contains iodine and/or kelp

Assuming you have Hashimoto's nether of these should be taken

drknews.com/iodine-and-hash...

For full Thyroid evaluation you need TSH, FT4, FT3 plus TPO and TG thyroid antibodies and also very important to test vitamin D, folate, ferritin and B12

Private tests are available. Thousands on here forced to do this as NHS often refuses to test FT3 or antibodies

thyroiduk.org.uk/tuk/testin...

Medichecks Thyroid plus ultra vitamin or Blue Horizon Thyroid plus eleven are the most popular choice. DIY finger prick test or option to pay extra for private blood draw. Both companies often have special offers, Medichecks usually have offers on Thursdays, Blue Horizon its more random

All thyroid blood tests should ideally be done as early as possible in morning and fasting. Do not take Levothyroxine dose in the 24 hours prior to test, delay and take 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)

If also on T3, or NDT make sure to take last dose exactly 12 hours prior to test

Boon79 profile image
Boon79 in reply to SlowDragon

Thank you. The supplement is Swansons Thyroid Support and doesn't contain iodine or kelp. I have stopped taking them though just in case. I am going to order a private blood test in a couple of weeks. On 2 grains of Thai Thiroyd I still feel very hypo. Struggling to speak properly, tired, bloated and slightly constipated. I am confused that as 100mcg of Levothyroxine is supposed to be the equivalent of 1.25 grains of NDT, why I still feel under medicated on 2 grains? I took my 17 year old daughter's resting pulse last night and it was 80bpm so maybe I'm reading too much into it?

SlowDragon profile image
SlowDragonAdministrator in reply to Boon79

Well you need good vitamin levels too for any thyroid hormones to work

Essential to test vitamin D, folate, ferritin and B12, not just TSH, FT3 and FT4

Do you have Hashimoto's? Diagnosed by high thyroid antibodies, if so are you on strictly gluten free diet?

Boon79 profile image
Boon79 in reply to SlowDragon

GP has never told me why I have hypothyroidism! Just given levothyroxine and tested by TSH. I will order private blood tests in a few weeks including ferritin, iron, B12 etc. Hopefully you wonderful people can help with the results x

in reply to Boon79

I think that you are reading too much into your heart rate. Mine has always been a little higher since on NDT but I have put that down to being slightly unfit.

Two grains of NDT are about 78 Levo and 18 T3, it does take a few weeks for your body to sort this new medication out.

A blood test showing FT3 in a few weeks will show you if your taking too much also if you are losing weight for no reason.

shaws profile image
shawsAdministrator

2 grains is stated to be around 200mcg of levothyroxine (in its effect) due to it containing more than T4 i.e. T3 etc.

When switching from levo to NDT, you can take an equivalent dose to levo and then every 2 weeks add 1/4 tablet and I will give you some links to copy/paste which may be helpful. One of our Advisers advised to not split doses as it's then better to find a 'window' for an optimum dose.

tinyurl.com/ycxpz565

tinyurl.com/ya5blrr2

tinyurl.com/y7ejh9sh

Boon79 profile image
Boon79 in reply to shaws

Yes, I started on 1 grain for 10 days, then increased by 1/4 grains every 10 days until I got to 2 grains. Still feeling hypo. I have raised to 2 1/4 today and will get a blood test in a few weeks. Thank you for the links. I've considered taking the dose in one go but do find a bit if a 'rush when the t3 kicks in x

shaws profile image
shawsAdministrator in reply to Boon79

We are all individuals and what suits one may not suit another.

The doctor who did the links above was also a scientist and researcher and only took one blood test for the patient's initital diagnosis. Thereafter it was all about the relief of clinical symptoms and titrating doses.

Blood tests do tell us where the results are, but not how we 'feel' and the majority of doctors only take notice of them and pronounce we're on sufficient whilst completely ignoring the symptoms of the patients and the aim is to relieve symptoms.

in reply to Boon79

Yes so do I, taking mine at 5am and 2 pm works well for me.

MaisieGray profile image
MaisieGray

Depending on whether you were on mono-Levo therapy before moving to Thiroyd, or combo T3/T4, you being at 2 grains may be too high too fast for you. There is no direct equivalancy between T4 and NDT but if you work on 38 mcg T4 and 9 mcg T3 per grain, and an estimated T3 = 4 X T4 (remember there's widely differing views on that) then you are taking roughly the equivelant of 148 mcg T4. However it doesn't really matter, in that if NDT is causing you symptoms at that dose, you'll want to address it, whatever the dose of T4 you were on previously. Normally it's suggested you reduce by quarter grains to the level at which you didn't have that symptom, stay on it a while then gradually increase again; but if I'm reading correctly and you started at 2 grains, reduce by perhaps quarter of a grain, and see if the symptom goes away, and if not, reduce by further quarters until it does, then gradually reintroduce it.

Boon79 profile image
Boon79 in reply to MaisieGray

I started on 1 grain for 10 days and then increased by 1/4 grain every 10 days until I got to 2. Still having hypo symptoms. I've read that 'most' people feel well on 2-3 grains of NDT so that doesn't tally to 1 grain being bio-equivalent to 75-100mcg of levothyroxine, as 2 grains would be more like 150-200mcg of levothyroxine? I guess it's trial and error.

I'll post my results in a few weeks.

Thank you for your response x

serenfach profile image
serenfach

One of my first symptoms if I am underdosed is a raised heart rate. Possibly due to only having one adrenal gland, but I can always tell if underdosed by the thumping in my ears!

Boon79 profile image
Boon79 in reply to serenfach

Yes, it was one of the first signs for me too. I'm hoping things will level out soon. One adrenal gland. Poor you!

Boon79 profile image
Boon79 in reply to serenfach

Sorry Serenfach (Welsh?) I just wondered what mcg of levothyroxine you were on and how much ndt you're on now? I was 100mcg levo 5 days per week and 75mcg on 2 days pw. I am now on 2.25 grains and get the ear-thumping you mention.

serenfach profile image
serenfach in reply to Boon79

I was on 250 levo, and took 2.5 grains NDT. I was on WP and then moved to Nature-throid when WP went off the market. All was well until earlier this year when the Nature-throid stopped working and my levels were very low (below range) which started the heart problems.

Boon79 profile image
Boon79 in reply to serenfach

Wow. I'm on 2.25 grains and was only on 100mcg of levothyroxine! Maybe you weren't taking enough?

serenfach profile image
serenfach

I judged it by how I was feeling with back up from blood results. I think I just converted the NDT much better than the thyroxine. My GP got jittery at the levels I seemed to need of thyroxine and would not go higher than 250, even through my TSH was around the 3 mark. He nearly had kittens when on NDT my TSH was 0.02!

When I was on thyroxine, I was back and forth to the surgery with various things and felt awful. He could not discount that since I changed to NDT I had not visited him once!

humanbean profile image
humanbean

Fast heart rate can be caused by low iron and/or low ferritin. I get this problem myself. I have to take iron supplements all the time to maintain my iron and ferritin levels as near to optimal as possible. Recently I've been taking 3 tablets a week, spread out throughout the week. I think I might need to increase to 4 soon because I'm getting a fast heart rate again.

Boon79 profile image
Boon79 in reply to humanbean

Thank you. I think I'llbuy some ferrous sulphate tablets from the pharmacy and take one every other day. Feeling great otherwise.

humanbean profile image
humanbean in reply to Boon79

It isn't a good idea to take iron supplements without knowing your ferritin and your iron level. Iron is poisonous in overdose. And if your ferritin is high and serum iron is low, or vice versa, it can indicate a problem that needs to be fixed before taking iron.

You could get your levels measured relatively cheaply with a finger-prick test :

medichecks.com/iron-tests/i...

The price quoted can be reduced with the appropriate discount code :

healthunlocked.com/thyroidu...

There are other special offers on Thursdays - so it would be worth checking those out to see if the price can be lower still.

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