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Thyroid UK
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Hypothyroid and palpitations?

Hello, I have hypothyroid and take 100 mcg synthroid, I was on 112 for 3 months but asked to go back to 100 mcg for 3 months as i was nervous, So i have been back to 100 mcg since Oct 2017, My question is can this change cause problems and can i have rapid heartrate about once a day around noon with hypothyroid, it is scary, goes to 124 a few times, mostly stays about 101 most of the day, goes down to 90 even 88 in the evening, (Heartbeats) is this something to do with hypothyroid? I get very sleep at night too, can hardly stay up past 9 pm. i am 59 yrs old and have had anxiety all my life too, i take ativan for that



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Can you post your recent thyroid results and ranges and say what dose you were taking when you had the tests? Being undermedicated can cause palpitations as well as being over medicated.


Last July labs were tsh 6.2 range 0.5-5.000

Free t4 1.37 range 0.70-1.80

went back in Oct and labs were

TSH 1.1.73

Free t4 11.55

in july i was given increase in synthroid from 100-112 mcg i went back in Oct as shown and asked to go back to 100 mcg as i thought i was feeling jittery

Now today 3 months later i keep having racing heart about once a day and very tired at night about 9 pm Have anxiety all my life too

just got tested today so i dont know the latest labs yet, probably in a few days



TSH 1.1.73 doesn't look right. Can you check and include the range?

What is the range for FT4 11.55?

Write a new post when you get the latest labs. Include the lab ref ranges too.


sorry about the typo the ranges are 0.05-5.000 for tsh and 0.70-1.80 for free t4

my labs were 1.73 TSH

1.55 Free t4

That is from test on Oct 25 2017

before this test on Aug 2 2017

they were T4 1.37

Tsh 6.20 with same ranges as above

Im waiting on yesterdays results soon

I was given 112mcg synthroid on august 2 2017 but when i went back in Oct 2017 i asked to go back to 100 mcg synthroid as i was jittery. I have always been on 100 mcg synthroid before the change in Oct , I am still on 100 mcg and have racing heart , that is why i wondered if it is possible to get that with hypothyroid,



If TSH 1.73 and FT4 11.55 were from when you were taking 112mcg I think you are probably undermedicated on 100mcg and that may be why you are having a racing heart.

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T4 was 1.55 not 11.55 sorry but i posted latest ranges and newest blood work results at tsh 3.05 and ft4 1.50


Last blood test a few days ago is TSH 3.05 range is 0,5-5000 and T4 is 1.50 range is 0.70-1.80



You are undermedicated to have TSH 3.05 and should request a dose increase.

The goal of Levothyroxine is to restore the patient to euthyroid status. For most patients that will be when TSH is 0.5 - 1.0 with FT4 in the upper range. FT4 needs to be in the upper range in order that sufficient T3 is converted. Read Treatment Options in thyroiduk.org.uk/tuk/about_...


Ok I will ask, Thanks so much



I'm hypothyroid and i was getting palpitations for about 6 months roughly....Im 60...I was on 112 synthroid a while back, but asked to go back down to 100's too....I was slightly out of doctors range on the 112's, but thats not when the palpatations happened (they came out of the blue later)....Im in doctors normal range I think Im just below 1.0 for my TSH reading...My blood pressure is slightly high, and was much higher on the 112 pill...Ive cut down on the caffeine (tea and coffee) and im using decaf coffee and herb tea..or real weak tea....and watching the salt on foods and in things...Im taking CoQ10 too...palpatations have stopped so far...fingers crossed.. PS/ Starbucks sells good decaf coffee...(in packages too)...So for me it might be blood pressure...

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