Low tsh

[Georgie03]

Hi ! I had a tsh blood test and it came out 0.16 . I know that it's very low. I am currently on 75 mg .Should I lower it to 50 mg or 25 mg ? Thank you!

[PurpleNails Administrator]

Not on TSH as its an unreliable measure. You need to test FT4 & FT3. FT3 shouldn’t be over range. Ideally FT4 shouldn’t either, but some need top of range FT4 to allow enough FT3 to be converted from it.

[Georgie03 in reply to PurpleNails]

Thank you for your advice!

[SlowDragon Administrator]

Just testing TSH is completely inadequate

Always test thyroid levels as early as possible in morning before eating or drinking anything other than water and last dose levothyroxine 24 hours before test

This gives highest TSH

Which brand of levothyroxine are you currently taking

Do you always get same brand levothyroxine at each prescription

Many people find different brands are not interchangeable

Most importantly, how do you feel?

Bloods should be retested 6-8 weeks after each dose change or brand change in levothyroxine

For full Thyroid evaluation you need TSH, FT4 and FT3 plus both TPO and TG thyroid antibodies tested.

Very important to test vitamin D, folate, ferritin and B12 at least once year minimum

Low vitamin levels are extremely common, especially with autoimmune thyroid disease (Hashimoto’s or Ord’s thyroiditis) diagnosed by high thyroid antibodies

Autoimmune thyroid disease with goitre is Hashimoto’s

Autoimmune thyroid disease without goitre is Ord’s thyroiditis. Both are autoimmune and generally called Hashimoto’s.

In U.K. medics never call it Hashimoto’s, just autoimmune thyroid disease (and they usually ignore the autoimmune aspect)

Have you had thyroid antibodies tested

Have you had vitamin levels tested recently

What vitamin supplements are you currently taking

Private tests are available as NHS currently rarely tests Ft3 or all relevant vitamins

List of private testing options

thyroiduk.org/getting-a-dia...

Medichecks Thyroid plus antibodies and vitamins

medichecks.com/products/adv...

Blue Horizon Thyroid Premium Gold includes antibodies, cortisol and vitamins by DIY fingerprick test

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 down to £26.10 if go on thyroid uk for code

thyroiduk.org/getting-a-dia...

monitormyhealth.org.uk/

NHS easy postal kit vitamin D test £29 via

vitamindtest.org.uk

About 90% of all primary hypothyroidism in Uk is due to Hashimoto’s. Low vitamin levels are particularly common with Hashimoto’s.

Link about thyroid blood tests

thyroiduk.org/getting-a-dia...

Link about Hashimoto’s

thyroiduk.org/hypothyroid-b...

List of hypothyroid symptoms

thyroiduk.org/if-you-are-un...

[Georgie03 in reply to SlowDragon]

Thank you for your reply!I need to reduce the dosage because I was pregnant and gave birth to a baby boy last year .My body obviously doesn't need as much levothyroxine as before .

[Georgie03 in reply to Georgie03]

This result proves how much my tsh dropped after childbirth.

[tattybogle]

Why do you think you need to reduce dose ?.... if it because you have been told that a low TSH has increased risks for bone / heart issues then be aware that it has been shown that there are no increased risks unless TSH is below 0.04 . (This was from a very large, long term study of real patients in Scotland)

Your TSH is well above the 0.04 level on your 75mcg dose .

So if you feel well on this dose, with no signs of overmedication, (fast heart rate , slight tremor in fingers . feeling hot, over-frequent bowel movements etc ) then just having a TSH of 0.16 is not in itself a reason to reduce your dose.

Have you previously been on a lower dose ? how did it feel ?

if you feel ok on 75mcg , but do decide you want to try a lower dose anyway ,then it might be better to just reduce slightly to 62.5mcg rather than 50mcg (either by alternating 50 mcg one day and 75mcg the next , or by cutting a 25mcg in half to get 62.5mcg each day )

To reduce dose to 25mcg would definitely be too much of a drop .

Obviously it would be much better if you knew what your fT4 and fT3 levels were. but NHS rarely test fT3 , and they seem to be doing less and less fT4 tests.

it's not a good idea to have fT3 over rage .

fT4 is a bit more of an unknown. some people on Levo just don't feel well unless their fT4 is a bit over range ( they need it there to get enough fT3) ..... but there is some recent research suggesting that T4 (both natural and from Levo) may have some role in cancer proliferation. So being cautious until we know more , then a high /over-range fT4 maybe isn't something you want to have unless you need it there to feel well .

please see me reply to this post (3rd reply down) healthunlocked.com/thyroidu...

It contains links to the study showing TSH between 0.04 -0.4 has no greater risks than TSH 0.4- 4.

It also has links to posts with useful discussions on the subject of low TSH /risk.

[Georgie03 in reply to tattybogle]

This result proves it how much my tsh dropped after childbirth.

[tattybogle in reply to Georgie03]

there is a period of rebalancing of thyroid hormone after a pregnancy/ birth , thyroid function can swing one way then the other .so for about a year afterwards, it's safe to assume 'anything might happen' .. especially if you already have autoimmune hypothyroidism.

So keep an eye on things. it might be that you need less at the moment , but it might not stay that way. it might go the other way later , and you need more again .

Do you feel overmedicated , or is it just that your latest TSH result is lower then it was before ?

if you don't feel overmedicated , but you still want to to reduce anyway , make it as small a reduction as possible and see how you feel on a little less for a couple of months.

[Georgie03 in reply to tattybogle]

My tsh is much lower than the last time I took a blood test ,in 4 months it dropped from 2 to 0.16 .I don't want to take more levothyroxine than necessary so I decided to change the dosage to 50 mg and do another blood test in 2 months time.Thank you for your reply!

[Georgie03]

Thank you for your reply! I was pregnant and gave birth last year and I obviously don't need as much levothyroxine as before . This result proves it how much my tsh dropped after childbirth.

[SlowDragon Administrator in reply to Georgie03]

Congratulations on your little boy

Possibly you might need less …..but the longer we have thyroid disease the less your own thyroid can make

When were vitamin D, folate, ferritin and B12 last tested

[Georgie03]

Thank you!I have decided to take 50 mg and do a blood test in 2 months time. I was tested for vitamin D,folate,ferritin and b12 during pregnancy last year.