Increase thyroxine in pregnancy resulted in hea... - Thyroid UK

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Increase thyroxine in pregnancy resulted in heart palpitation


Hello all, I need some advice!

I’ve underactive thyroid been on 25mcg dose for a while, this was increased to 50mcg as I was feeling very tired. At increased dose I felt better but then started to notice my heart started to skip a beat, so I went back to 25mcg.

I just found out I’m pregnant and my GP said to increase the dose back to 50mcg as needed for the baby but then I’m back to having heart palpitations/skipping beats - what do I do reduce the dose back or live with strange heartbeat?

23 Replies

Sometimes when we're given a low dose, i.e. 25mcg it isn't sufficient and our heart and brain need the most levothyroxine and our heart can act up a bit. Unless you had a heart problem previously 50mcg is a starting dose.

Your body might well settle down in a few days with your new dose but if it doesn't phone your GP and tell him. Or you can halve a 25mcg tablet and add to your original dose (25mcg) for a week and see how you get on. Slow increases are sometimes needed.

Asterisk90 in reply to shaws

Thank you for the tip the slow increase seems to have worked perfectly!

Ask your doctor to test vitamin and mineral levels. It's common for people with autoimmune thyroid disease to have low vitamin levels and it could cause problems with dose increases. Test folate, ferritin, vitamin D and vitamin B12. Also check with GP if it's alright to take magnesium supplements as it can help heart rhythm. Folate is very important for babies development. Ask GP if thyroid antibodies have been tested and if not ask for TPO and TgAb to be included in tests.

If you get a copy of your last thyroid test results and post them here, we can explain them to you. Always keep a copy of all blood tests and ensure the results include lab ranges which we need to interpret results.

Sorry to alarm you but I wouldn't let levothyroxine near my unborn baby I would be more concerned that I had enough iodine to support myself and baby

iodine deficiency is the number 1 preventable cause of disabilities in babies

Obvs if you have hashimoto then careful handling is needed in your case but if you are one of the growing number of people who are deficient in iodine and have developed hypothyroidism as a consequence of that then eat lots of iodine rich food like cod sardines bladerwrack seaweed and ween yourself of levothyroxine

I don't think you should be advising a newly pregnant woman to wean herself off thyroxine and start upping her iodine levels without first testing to see what they are.

Your advice could cause serious complications, like miscarriage! Now is not the time to be "alternative".

They give iodine to livestock to stop them having stillbirths that's why meat contains iodine

Asterisk90 should do some serious research

Humans and livestock are not interchangeable! It's dangerous advise to tell someone to wean off thyroxine when they're pregnant. Iodine deficiency is not the no.1 cause of hypothyroidism in the UK.

I have since learned that Asterisk90 has hashimotos disease but I still maintain I would not take levothyroxine if I was pregnant

It' s up to Asterisk90 what she does and I wish her well

That's funny I don't see any mention of humans and animals being interchangeable in my answer ?

Iodine deficiency is a serious problem in uk

helvellaAdministrator in reply to lillyofthevalley37

12. Members posting on Thyroid UK must only post information which is true and correct to their knowledge. If relevant, please provide references to health or medical information.

helvellaAdministrator in reply to lillyofthevalley37

One of the problems that has been discussed here recently is how research papers use population statistics and medics apply them to individuals. That is precisely what you are implying Asterisk90 should do - take your comment about iodine deficiency across the population and apply it to her specific, individual case.

Actually my daughter was on levothyroxine and I saw what it did to her

I dread to think what it would do to an unborn baby

helvellaAdministrator in reply to lillyofthevalley37

My comment was referring entirely to your comment about iodine.

However, we have had many good results reported by women who took levothyroxine during pregnancy. It is inappropriate to take the specifics of your daughter and make a blanket recommendation.

RedAppleAdministrator in reply to lillyofthevalley37

So was your daughter hypothyroid? And if yes, what was the cause? Does she take anything instead of thyroxine?

RedAppleAdministrator in reply to lillyofthevalley37

it is very true that a minority of hypothyroid people do not do well on synthetic thyroxine (T4). Sometimes they need to add some liothyronine (T3), or take desiccated thyroid instead. But unless their hypothyroidism is caused solely by iodine insufficiency, it's likely they will need to take some form of thyroid hormone replacement to have any quality of life.

An unborn baby needs to obtain thyroid hormone from the mother at least until they have developed their own working thyroid. To deny the unborn child thyroxine (which ,incidentally is what a healthy thyroid produces - but naturally, not synthetic), is to risk not simply miscarriage, but a whole plethora of physical and mental abnormalities. I'm quite sure you would not wish this for any pregnant woman.

it seems to me that people with hashimotos are not being treated for an over active immune system - probably bc they don't know how to - they only treat the symptom in this case hashimotos with the horrendous levothyroxine

the thought of desiccated animal thyroid is gross but I would rather that than levothyroxine

you are obvs aware that thousands of people are anti levothyroxine

"You are obvs aware that thousands of people are anti Levothyroxine"

And many thousands are very well on Levo, you cannot label it "horrendous" just because your daughter didn't get on with it.

And way more are very well on it and not cluttering up the forums and groups with horror stories. Did your daughter try different brands? That can often make a difference because we are all different.

helvellaAdministrator in reply to lillyofthevalley37

If you are insisting on looking at veterinary medicine:

HORSES need less iodine (mg/kg body weight) than ruminants. In particular, avoid the use of excessive I-supplement in mares in late pregnancy, or young foals. Toxic goitre can arise if those animals ingest excessive amounts.

Hello I do have hashimoto so I’m generally not advised iodine....

Getting vitamins high can help your body and the baby as well but often if levels are low we can have problems increasing the dose. Congratulations about the baby though but make sure the hospital knows you are on thyroid meds so that they can make sure levels are right for you both! You will probably need an increase as baby grows.

I'm assuming you mean T4, Levothyroxine and not T3, Liothyronine? I've been on both but I am not a pregnant woman so pay me the littlest attention of those who reply to you, however, I believe that T3 may be of an assistance, but only because it has helped many others, including myself but, read all these comments and then make a judgment, and don't forget to tell your endo exactly how you feel. Peace be with you.

When I was on the very low doses you are talking about, I struggled mightily to get my dose raised. I had anxiety, panic and lots of heart flutters and skipped beats and speeded up bits. The move to 100mcg a day was much easier. In fact I don't think I had any side effects that time.

I couldn't cope with the 25/50 alternate days at all either. If anything that made my anxiety worse. So I used a pill cutter and went from 25 to 50 via 2 weeks of 37.5mcg a day. The 2 weeks was enough to allow me to then go up to the 50mcg a day without issue. Then I started counting the 6 weeks and arranged my next blood test.

I hope that idea can help you.

And I worked (still am working) on raising my vitamin and mineral levels at the same time.

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