Dose increases but TSH rising and T4 and T3 falling

[Pearlteapot]

Hi everyone.

I have been gradually increasing my dose of levothyroxine. After an increase I feel better for a while then worse. Over time, the more my dose has increased the worse my biochemistry seems to be. I wondered if anyone could help me to understand what is going on.

I started off with a very high TSH of 71 and am leaving out of my account the early period from March 2022 when I was started on levothyroxine and my TSH reduced from 71 to 5.48. However, from then on:

23/5/22 75mcg levo

TSH 5.48 (0.3 - 4.2)

T4 18.2 (12-22)

21/6/22 - 75/100 mcg levo since last test

TSH 3.04

T4 16.9 (12 - 22)

T3 4.54 (3.1 -6.8)

30/6/22 75/100 mcg levo since last test

TSH 1.57

T4 18.4 (12 -22)

T3 4.3 (3.1 - 6.8)

10/08/22 (still 75/100)

TSH 2.21 (Range: 0.27 - 4.2)

T4 15.2 (Range: 12 - 22)

T3 3.91 (Range: 3.1 - 6.8)

20/8/22 100/75/100mcg levo since last test

TSH 2.43 (0.27 - 4.2)

T4 16.9 (12-22)

4/10/22 100/125 mcg levo since last test

NHS Test

TSH of 2.51 (0.3 - 4.20)

T4 of 14.6 (12.0 - 22.0)

Private Test (Lets Get Checked)

TSH 3.16 (0.27 - 4.2)

T4 14.6 (12.0 - 22.0)

T3 3.1 (3.1 - 6.8)

So since June I have increased the dose from 75/100 to 100/100/75 to 100/125 and my TSH has gone up instead of down, my T4 has gone down and my T3 has gone down to bottom of the range.

All tests are done at 9am or very close to then, after fasting, no vit B or Biotin for a week prior and no levo for 24 hrs. I haven't tested vitamins since 10 August when it was

Folate - Serum 18.83 ug/L (Range: > 3.89)

Vitamin B12 - Active 71.2 pmol/L (Range: 37.5 - 150)

Vitamin D 86 nmol/L

Does anyone have any idea what might be going on please?

I have also been diagnosed positive for compound hemochromotosis and have elevated transferrin saturation rate but normal ferritin. I am also positive for the DIO2 gene but my endo says this test is fairly meaningless.

Best wishes and thanks in advance.

Cx

[SlowDragon Administrator]

Helpful profile info

Which brand of levothyroxine are you currently taking

Do you always get same brand levothyroxine at each prescription

Do you normally take levothyroxine waking or bedtime

Approx how much do you weigh in kilo

You could simply be under medicated ….your results certainly suggest you are

Have you had coeliac blood test done

Are you on strictly gluten free diet or dairy free diet

do you wear a Fitbit or equivalent

[Pearlteapot in reply to SlowDragon]

Currently taking Accord 100mcg and Mercury Pharma 25mcg.

Until August it was Mercury Pharma for both.

Since August I've been taking it at bedtime.

I;m 76kg

I was on strictly gluten and dairy free until this last fortnight when I lapsed a bit

I wear an apple watch and have an average RHR of 50 which is a slight improvement. Even now my heart rate can go down to 41 while working at my desk. I have had two 24 hour monitor tapes in the last 3 months and both were fine, no issues identified. I used to have palpitations when my dose was 75/100 but no longer suffer from them.

My TSH suggests that I am still undermedicated but what I can't understand is why it it going up and my t4 going down?

[SlowDragon Administrator in reply to Pearlteapot]

Suggest you try to get Mercury Pharma for 100mcg at next prescription

Low Ft3 will result in low stomach acid…..leading to poor absorption of levothyroxine

initially worth trying increase in levothyroxine

Lots of people need higher dose than guidelines of 1.6mcg per kilo of your weight per day …..especially if you have poor absorption

academic.oup.com/edrv/artic...

Endocrinologist could prescribe liquid levothyroxine. Usually taken as split dose morning and afternoon

If Ft3 remains low once Ft4 is in top third of range….Likely to need addition of T3 prescribed alongside levothyroxine

[Pearlteapot in reply to SlowDragon]

consultant this afternoon increased my dose to 125mcg. My concern is that increases to date are not raining my T4 level but rather it’s decreasing. I’m talking to him again later this evening.

[radd]

Pearlteapot,

A mutation on the DIO2 gene is not meaningless if it inhibits conversion enough never to achieve wellbeing.  It offers insight into how our thyroid workings are and confirmation of a possible need for T3 meds once an optimised Levothyroxine dose fails to convert to adequate T3. 

I presume those results relate to 'free' hormone and not totals? All that T4 you are medicating has to be going somewhere. We have discussed haemochromatosis previously so that leaves having TBG and SHBG tested? These are thyroid and ovarian hormone transporter proteins that risk binding too much ‘free’ when in excess. 

This would induce hypothyroidism, ie raising TSH and reducing FT4 that would reduce FT3 levels regardless of what meds you take, as per your results.

[Pearlteapot]

Hi radd, I will look into the SHBG testing. I thought that being hypo reduced SHBG whereas the excess binding comes from too much SHBG. I suppose its possible from my HRT patch so I'll look into it.