Medication by weight

[Dakie]

Hi, how do you find the dose of medication depending on your weight?, I am currently on 50mcg of levothyroxin, due this month for another blood check, my current weight is 10 st 3 lbsMany thanks

[Regenallotment Ambassador]

hi it’s a bit of a broad brush approach as all metabolisms and gut absorptions aren’t equal but the NICE guidelines for Auto Immune dosage suggest around 1.6mcg per kg of body weight. I’m 66kg which is 10 stone 5 (I think… I googled the conversion).

66x1.6 = 105.6mcg as a guide.

Current dose 125mcg Levo after 8 weeks TSH slightly under range FT4 high in range FT3 stubbornly 35% through range. Feels about right for me. Certainly wouldn’t want to take any more T4.

I’ve just doubled down on the paleo low carb diet and upped my good fats and lost 700g this week. I expect if I can shift this last few kgs I’ll need to drop my T4 down.

Hope that helps, just remember we are all different and all have different vitamin status and absorption situations.

I started on 25 and was left on it for months till I found out about being optimal here. I’ve gone up by 25mcg every 8 weeks since.

🌱

[Dakie in reply to Regenallotment]

Thank you for your response

[helvella Administrator]

I have written a piece about this - and included a spreadsheet for calculating.

But there are factors which make it a very questionable approach. Yes - a heavier person will require more than an otherwise identical person who weighs less. But that does not imply you can accurately calculate a dose.

helvella.blogspot.com/p/hel...

[Ellie-Louise in reply to helvella]

Thank you, that was useful to know.

If you were to mention NICE to a doctor, would you pronounce it NICE or N.I.C.E please?

[helvella Administrator in reply to Ellie-Louise]

I'd say it as in a nice way!

Adding "NG145" - which is the ID of the thyroid guidelines!

[Ellie-Louise in reply to helvella]

Thank you, that’s nice to know. 😉

[helvella Administrator in reply to Ellie-Louise]

I'm just a patient. What would I know.

[Ellie-Louise in reply to helvella]

I think you’re very patient. 😇

[Dakie in reply to helvella]

Thank you, interesting read

[SlowDragon Ambassador]

How long have you been on 50mcg levothyroxine

Which brand of levothyroxine are you currently taking

Do you always get same brand levothyroxine at each prescription

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

ALWAYS test thyroid levels early morning and last dose levothyroxine 24 hours before test

ESSENTIAL to get all four vitamins at optimal levels

Low vitamin levels tend to lower TSH

(all many medics inappropriately look at)

Previous post showed low vitamin levels

healthunlocked.com/thyroidu...

Low vitamins are DIRECT RESULT of being left on only 25mcv Levo

what vitamin supplements are you currently taking

Have you retested vitamin levels

[Dakie in reply to SlowDragon]

HiI have been on 50mg since the 28th Dec last year after my TSH come back as 5.44, unfortunately that was the only test they did. I am retesting in a couple of weeks and will ask for full check. I always get the same brand 'Mercury Pharma'

Have also been taking Thornes basic B complex, 1 a day and vit D3+K2, 5 drops a day since our last chat.

Health wise not great, I now have cold feet that actually hurt!, and a pulse like sound in my ear!, amongst all the usual stuff!

[SlowDragon Ambassador in reply to Dakie]

insist on vitamin D, folate, ferritin and B12 are tested too

Likely low as direct result of being left on too low a dose Levothyroxine

Low vitamin levels tend to lower TSH

Essential to maintain OPTIMAL vitamin levels

[Dakie in reply to SlowDragon]

Seeing the GP on Wednesday, I have my list of demands!

[SlowDragon Ambassador in reply to Dakie]

Levothyroxine doesn’t “top up” failing thyroid it replaces it

Hence essential to be on high enough dose

Likely ready to increase to 75mcg

Retest again in further 2-3 months after increasing to 75mcg

[SlowDragon Ambassador]

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

List of private testing options and money off codes

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

bluehorizonbloodtests.co.uk...

Monitor My Health also now offer thyroid and vitamin testing, plus cholesterol and HBA1C for £65 

(Doesn’t include thyroid antibodies) 

monitormyhealth.org.uk/full...

10% off code here 

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

Only do private testing early Monday or Tuesday morning. 

Watch out for postal strikes, probably want to pay for guaranteed 24 hours delivery 

Link about thyroid blood tests

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

Link about Hashimoto’s

thyroiduk.org/hypothyroid-b...

Symptoms of hypothyroidism 

thyroiduk.org/wp-content/up...

[Sleepman]

Thankyou Helvella interesting

I had a TSH of 78 in early October when diagnosed and was disappointed to be started on 50 mg and told it would be 8 weeks till new blood tests. I am under 65 and heart is ok. I managed to get a test at 5 weeks and moved upto 100 mg. With such a high TSH,I suspect my thyroid was doing nothing.

I am now on 150 mg and that sits on 1.6 mg/kg nice guideline. I started feeling better at 125 mg.

I have been working on vitamins since week 5 . Vit D and B complex as per advice from the kind people on here.

[helvella Administrator in reply to Sleepman]

Indeed! The formula can produce a sensible value which works for some.

The trouble is some need far, far more, others (like me) need less. And changing make can change how much you absorb - thus throwing out the calculation.

[Sleepman in reply to helvella]

I take your points. It should be flagged as very rough guide value to be refined based on symptoms when on this dose.

My issue was being put on a very low starter dose (50mg)when already feeling crap for a very long time and desperately wanting to get better.

I feel my whole NHS/Doctor experience since finding out I have underactive thyroid has been pretty poor. I was worried, I would be going up in 25 mg jumps every 8 to 10 weeks, if bloods are done every 6 to 8 weeks.

I "pushed" the doctor to speed up but how many suffer for a lot longer than they need to. Not so easy with a foggy brain and extreme fatigue.

No warnings about blood tests and no levo dose until after bloods that day and not to take Biotin for 2 or 3 days before testing.

I think all newly diagnosed should have FT3 measured/screened several times to make sure they convert levo properly rather than letting people suffer. Vitamins need checking as well as other body functions / organs that have been running on empty/struggling.

[helvella Administrator in reply to Sleepman]

I think everyone should have FT4 and FT3 (and TSH) all done, every time!

[McPammy]

if I was on a dose relating to my weight I’d be way over medicated. Not sure if this scenario would work for everyone. I check my dose by blood test results of TSH, T4 and T3.

[Digger0]

I'm 63 kg and have 100/125 Levo on alternate days. I had RAI to destroy my thyroid.