How long does it take for TSH levels to rise or fall following an increase or decrease in levothyroxine?

[Mickeydooley]

Following another review appointment at the endo clinic my meds have been kept the same as last time even though I still have ‘hypo’ symptoms. This is due to the fact that for the second time in a row my TSH is suppressed at 0.02 (0.27-4.2). My t3 levels are 65% through the range and T4 is 36% through the range. The levels don’t seem too bad but I’m still feeling very cold, anxious, very tired, no motivation to do anything and quite low mood. I’m currently on 75mcg levo and 20mcg t3. I was disappointed that the endo didn’t increase my dose of levo as he said in his letter to the gp that even though my TSH was suppressed I did not appear to him to be over replaced. (He commented on my very cold hands). I have to go back to see him in four months.

My questions are:

1. If I increased my levo by 25mcg (to 100mcg) now would I have time between then and now to get my levels back down again if I felt over replaced? How long does it take for TSH levels to rise and fall?

2. Would an increase in levo further reduce my TSH levels and is that a problem?

3. Would I be best just to leave things as they are for now? (I had a very stressful 6 months and the stress levels have reduced significantly so perhaps things will improve on their own?)

I’m afraid to make things worse but I’d like to see how I fare on an increased levo dose. I just hate going behind the endo’s back as he has been generally very supportive.

[SlowDragon Administrator]

Recommended on here that all thyroid blood tests should ideally be done as early as possible in morning and before eating or drinking anything other than water .

Last dose of Levothyroxine 24 hours prior to blood test. (taking delayed dose immediately after blood draw).

when also on T3, make sure to take last 5-10mcg dose 8-12 hours prior to test, even if this means adjusting time or splitting of dose day before test

is this how you do your tests?

Did you retest your vitamin levels or get cortisol and DHEA saliva test?

healthunlocked.com/thyroidu...

How about trying smaller increase in levothyroxine....

75mcg /100mcg on alternate days

Retest in 6-8 weeks

[Mickeydooley in reply to SlowDragon]

The endo clinic only operates in the afternoon unfortunately. I do the 24/12 hour spacing of meds before the tests. My last vitamin tests were done in July 2019 and I haven’t redone them since. Your idea of alternate days seems good. I just wondered if I felt over replaced how long would it take to get levels back down before I have to go back to clinic so that TSH levels aren’t worse. I’ll make sure if I have to reduce again that I do it a good 8 weeks before the next appointment. Thank you.

[Mickeydooley in reply to Mickeydooley]

And I bought the cortisol test but just haven’t done it yet.

[SlowDragon Administrator in reply to Mickeydooley]

Suggest you get vitamins tested first

[Mickeydooley in reply to SlowDragon]

How often do I need them retested? It was only 6 months ago that they were done.

[Mickeydooley in reply to Mickeydooley]

And I absolutely hate doing finger prick tests as I don’t seem to bleed well even after a hot shower and exercise! 😩

[SlowDragon Administrator in reply to Mickeydooley]

What were your actual vitamin results 6 months ago?

What vitamin supplements do you currently take?

[Mickeydooley in reply to SlowDragon]

All good except vitamin d slightly low. Have been supplementing with vit d since (although I do forget sometimes)

I currently also take magnesium

Ferritin 152 (13-150)

Folate 19.8 (>3.89)

Vitamin b12 99.2 (37.5-188)

Vitamin D 62.4 (50-175)

[SlowDragon Administrator in reply to Mickeydooley]

Perhaps just retest vitamin D

Very easy....just four drops required

vitamindtest.org.uk

[Mickeydooley in reply to SlowDragon]

I’ll do that although I wonder if low vitamin d would account for my symptoms?

I got the saliva test a while back on advice here because I was experiencing shakes and it was suggested that it may be to do with cortisol. I don’t have shakes every day and they’re not as bad as they once were (maybe due to the fact that my stress levels have reduced significantly?) so I thought I’d do the test as I bought it anyway.

Thanks again for your advice.

[SlowDragon Administrator in reply to Mickeydooley]

Vitamin D is actually a pre-steroid hormone

Shakes early morning and improving through day suggests adrenals

[Mickeydooley in reply to SlowDragon]

And would the cortisol test be appropriate then?

[SlowDragon Administrator in reply to Mickeydooley]

Yes....but if the stress you were under is now stopped and improving perhaps wait a bit longer before testing

Watch out there isn’t a “use by” date on the test

[Mickeydooley in reply to SlowDragon]

Ah! Didn’t think of that. I’ll check! Thx

[diogenes Remembering]

TSH response can be weeks, months or not at all. The phenomenon is called hysteresis

[Mickeydooley in reply to diogenes]

Thank you. I’ll have to look that up! I’ve only ever had 2 suppressed TSH readings since I was diagnosed in 2007. The endos are very nervous about it. I’m being sent for a DEXA scan next month.

[diogenes Remembering in reply to Mickeydooley]

T his paper describes the phnomenon of TSH hysteresis: open access:

A Review of the Phenomenon of Hysteresis in the Hypothalamus–Pituitary–Thyroid Axis

Melvin Khee-Shing Leow

Published on 14 June 2016

Front. Endocrinol. doi: 10.3389/fendo.2016.00064

[Mickeydooley in reply to diogenes]

Thanks for the info. Very interesting

[Goddess007 in reply to diogenes]

Thank you for this @diogenese ! Great paper & exactly what I was researching (delayed TSH response) and couldn't find anywhere else.

[Caroline888 in reply to Mickeydooley]

Hi Mickey

It might not be the same in your case but my surgery arranged for me to have a DEXA scan. I hadn't asked for it and hadn't even been to see a GP recently. When I phoned the surgery to query this, I was given to understand that a DEXA scan is routine for patients with certain conditions, one of which is underactive thyroid. My TSH is not suppressed so that wasn't the reason for it.

I hope that you soon start to feel better now that your life is less stressful.

Best wishes

Caroline

[Mickeydooley in reply to Caroline888]

Thanks Caroline! It has been a very difficult 6 months for me but things are calming down now. The DEXA scan was ordered as a face saving exercise (I reckon) by an endo at the clinic who wanted to reduce my meds on the basis of a suppressed TSH. I queried his decision and he agreed to leave my meds as they were as long as I agreed to a DEXA scan. X

[Nanaedake]

Thyroid hormone takes 6 to 8 weeks after dose change to register full effect in blood tests. As your FT3 ig reasonable within range, your symptoms could very likely be attributable to other factors like low vitamin, iron levels or another problem. These factors need to be excluded. Having too much or too little thyroid hormone can impact the heart, bones and other organs.

If it were my results, I'd want to rule out other factors before tweaking levothyroxine again when levels are stable and TSH low as changes in thyroid hormone can make me feel quite unwell.

[Mickeydooley in reply to Nanaedake]

How often do I need to do vitamin testing? I had all done on an ultravit test in July. Didn’t think I’d need them done again so soon. Thanks for your reply.