Is my dose too high or is this normal? - Thyroid UK

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Is my dose too high or is this normal?


I had a Total Thyroidectomy 2 weeks ago and I have been feeling quite well apart from being tired. I am on 125mcg of Levothyroxine and I have gone back to work today. I don't know if this is a coincidence or not but I have been suffering heart palpitations all morning. I had one heart palpitation on Sunday, then yesterday I had 2 but I just presumed it was nothing as I know I am still adjusting but today I just feel really anxious. Work has been absolutely fine though so I don't know what is going on.

10 Replies

Anxiety is something people sometimes experience in the stage of adjusting to levothyroxine. However, it may be due to poor nutrient levels as low calcium, B12, folate, ferritin or vitamin D and some minerals may cause symptoms of anxiety or palpitations.

Do not take multivitamins but rather, ask doctor to test bloods for all vitamins and minerals. When you have results then post them here for best advice.

Docs often say all is fine if within normal lab range but bumping along bottom of range will not make us feel well when losing our thyroid gland. Optimal vitamin levels are needed for thyroid hormones to work effectively.

Good sleep and hydration is also important.

You need TSH, FT3 and FT4 testing in 4 weeks and adjust dose if needed. It takes 6 weeks for any dose change to be fully adapted. Keep retesting every 6 weeks until on the right dose for you.

Are you saying that you were started on 125 mcg from nothing? That may be causing your palpitations, depending on what was the situation before your TT - were you taking hypothyroid meds before and had a TT to remove nodules/cysts, or were you hyperthyroid and on thyroid-suppressing meds?

I was hyperthyroid and on a low dose of Carbimazole (5mcg every other day). I was on Block and Replace 2 years ago before I came off it to see if my Graves's Disease had gone in to remission, it didn't so I went on Carbimazole on its own. I haven't had Levothyroxine since then. My levels were good before my Total Thyroidectomy. I am also on a daily dose of Vitamin D (800ui) which I've been on for about 2 years now as well.

So if you haven't had Levo for 2 years, and were taking Carbizamole, then started taking Levo at that dose, it may very well be causing your palpitations, which themselves can cause anxiety of course.

Have you retested your Vit D level, and your other nutrients, recently?

No, they haven't been retested since September. I'm still suffering with heart palpitations and it's been constant since Thursday. I am tempted to book an appointment with my GP as I'm not sleeping well because of it.


You will need full Thyroid testing after 6-8 weeks on constant dose of Levothyroxine

That's TSH, FT4 and FT3. Also extremely important to test vitamin D, folate, ferritin and B12

Ask GP to test vitamins now

Low vitamin levels are extremely common

Recommended on here that 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)

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

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

Which brand of Levothyroxine are you taking?

Many patients do NOT get on well with Teva brand of Levothyroxine. Though it is the only one for lactose intolerant patients

Many people find Levothyroxine brands are not interchangeable.

Once you find a brand that suits you, best to make sure to only get that one at each prescription. Watch out for brand change when dose is increased or at repeat prescription.

Always take Levo on empty stomach and then nothing apart from water for at least an hour after. Many take early morning, on waking, but it may be more convenient and possibly more effective taken at bedtime.

Other medication at least 2 hours away, some like HRT, iron, calcium, vitamin D or magnesium at least four hours away from Levothyroxine

You need vitamin levels optimal for good thyroid function. Many/most of us need to test and supplement some or all of these regularly to maintain good levels

Important to test FIRST before starting supplements

Also look at strictly gluten free diet.

Ideally ask GP for coeliac blood test first, if not already gluten free

125 mcg sounds like an average replacement dose for someone who has had a TT. I have half my thyroid and am on 120mcg of levothyroxine and I'm tallish, average build. Of course it depends on weight, height and other factors. You will need a blood test in 4 weeks time to find out if you need a dose adjustment.

I am 5'10" and around 160 pounds, so I would have thought 125mcg would be fine but the anxiety and heart palpitations I am suffering are terrible right now.

SlowDragonAdministrator in reply to RhubarbAndCustard

Which brand of Levothyroxine are you taking?

If it's Teva, this brand upsets many people

Do you make sure you take Levo on empty stomach and then nothing apart from water for at least an hour after

Getting vitamins tested by GP too

Hello, my favourite sweet,

I'm with Graves and had RAI in 2005.

Graves is an autoimmune disease and as such it is for life.

The thyroid is a major gland and when attacked by your Graves antibodies can cause very serious symptoms, as I'm sure you know and probably experienced.

Living without a thyroid comes with it own set of problems, least of all getting the two most appropriate hormones replaced that you have now lost.

It is early days for you, but should just like to say that a fully functioning thyroid would give you approximately 100T4 and 10 T3 daily - so personally I believe both these hormones need to be on prescription to enable a ratio between these two hormones to be achieved with your medication titrated accordingly until your health is stable and you are symptom less of hypothyroidism.

As previous detailed vitamins and minerals as well as a full thyroid evaluation need to be maintained at regular intervals until you feel a level of wellness that you find acceptable.

Graves Disease A Practical Guide by Elaine Moore - there is also a very comprehensive website - it's USA based so medical protocol somewhat different :

Hyper to Hypo to Healing - Barbara S Lougheed - debunks TSH read for Graves :

Your Thyroid and how to keep it Healthy - Dr Barry Durrant- Peatfield -

All the above authors actually have the disorders they have written about :

All the above have been and are, my goto books on my learning curve.

Take it easy, this is major surgery, look after yourself -

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