Dose related to weight

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Hi - Having been diagnosed with hypothyroidism some 18 months ago, I have never felt completely well despite being on thyroxin. My blood test continues to read as okay which does not match with the way I feel. sad However, I have read quite a few times, articles written by endrocologists in which they write that the thyroxin dose should be adjusted to the weight of the person, ie the heavier you are the higher your dose of thyroxin should be. Having compared my weight with my dose it appears that I should be on a dose of 200mcg daily, rather than the 125mcg which I am currently taking - I highered my thyroxin myself from 100mcg to 125mcg and told my doctor afterwards, but still did not feel much better. Maybe this weight/dose approach might work for some and not for others, as too much thyroxine coud make you hyper and ill. Does anyone have any thoughts or information on this matter. :?: Larks.

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  • Posted

    Hi -

    Have never heard about the dosage being tritated with weight.

    Will ask the consultant endocrinologist where I work.

    Personally can't see how this would work as you would surely end up HYPERthyroid if you doubled your dosage ? I seem to be very sensitive to even the smallest change - have recently had a blood test which showed I wasn't taking enough (knew there was a reason for my low mood and what my colleagues call my EEYORE syndrome !!) Increased my dose and am now

    having signs of being HYPER (poor sleep, twitchy,poor concentration etc........) Another thing to bear in mind is how other drugs can affect the absorbtion of thyroxine - even indigestion remedies !!

    Can honestly say I never realised the impact all this can have on your life-

    I am a registered nurse and feel less blase about hyper/hypothyroidism.


  • Posted

    Hi Dee - Thanks for your interesting comments - I suspect the reasoning behind the weight/dose approach might be that if a patient still does not feel well on their current dose of thyroxin, then the doctor might consider raising their thyroxin very gradually using the weight/dose guidelines. Would welcome feedback on your endocrinologist's comments on the matter.

    As you say, this approach would have to be minuscule, as thyroxin is a hormone and could be dangerous if taken in excess. Have you tried halving/quartering your lowest dose tablet.

    Also, like you I sense when I might need more thyroxin as I start to feel depressed and weepy (for no reason) and very tired. :cry: It is incredible that just the slightest imbalance could make us feel so awful.

    Thankyou - yes, I do know that some drugs can affect the absorbtion of thyroxin. I also read that I would need to take extra calcium daily, as your body uses calcium from the bones to help utilise the thyroxin into the different components of T3, T2 etc. This advice does seem to make sense.

    Over the past 18 months I have learnt to live with my underactive thyroid. I have good days and bad days (the bad days follow when I try to do too much). But why does it have to be this way :?: Some ladies manage to achieve a happy lifestyle having found the right medication.

    For any other ladies who might be reading this and would like to lose some weight - I have recently joined Slimming World and the Original/Red days seem to work well if you want to lose weight quickly and painlessly. Larks.

  • Posted

    Hi Larks,

    Advice from my colleague/doctor at work was to TRY to keep weight stable

    and I get my bloods checked regularly. (which is easy for me working in a hospital but your GP

    shouldn't begrudge you a few blood tests!) :roll:

    Also not to aim for the LOW side of the normal range Sure you know but NORMAL is 0.49 - 3.95

    Two weeks ago I was feeling awful TSH was 12.44 So increased Thyroxine from 75 mcg to 100 Now 0.62 Which is in normal range but am very twichy

    (?) poor concentration and painful legs. so am going to try 100/75 on alternate days. Then check bloods again. sad

    The secret is knowing your own body - but I don't always recognise the signs but getting better at it :?

    Do you think exercise has any effect ?

    One more thing (this is getting like \"War and Peace\" -sorry) :!:

    I have had the feeling of a lump in my throat - a scan to see if I had an enlarged thyroid was normal - it seems to be improving with more thyroxine..... have you ever heard of this side effect? Or am I mad :oops:

  • Posted


    I have the same lumpy feeling as you, you are not going mad, I believe it is because we both have a slight goiter that is not visible...but inside it is affecting our swallowing and causing the sensation that we feel. it should go as your levels drop.


  • Posted

    Thanks Jack-

    Have been so worried - GP said stress - STRESS WHAT STRESS ???? :shock:

  • Posted

    Hi Dee

    Thanks for the info re dose related to weight and keeping weight stable. I am in the process of losing weight with Slimming World. Have already lost 7lbs approx in 2 weeks, though my weight seems to be going up and down very erratically - I know you are not suppose to weigh yourself daily but I am so neurotic about losing all my flab donut: . Also I feel awful, :cry: all my old symptons returned this morning ie the extreme breathlessness, very weepy and so tired, but all calmed down a couple of hours after I took my thyroxine dose. The surgery are going to check my bloods at the end of next week. I am completely baffled as my previous blood tests taken at 12 week intervals have always read okay. I did drive up to London during the week to see my sick daughter (also a hypo sufferer) so maybe that was the reason why I feel so lousy or maybe losing weight is stressful to the body :!:

    What is so interesting is the way you are feeling tending towards feeling hyper and yet your blood tests are stable. Maybe the adjustment is just a bit too strong - your certainly sound hyper which can be very unpleasant. I think the tablets should come in lower doses than the 25mcg. because chopping that 25mcg. in half can be very hit and miss. I am well at the lower end of the scale ie TSH 0.04 and yet I have a low pulse rate and am always falling asleep. Now doesn't that just go to prove that every individual is so different and yet we are all expected to stick to a specific thyroxine dose according to the ranges set out in the main blood test.

    I have heard that exercise does help, BUT I did read on this website about 1 year ago, that a young chap who took up running needed to double his intake of thyroxine because of the running. Maybe gentle exercise would help like walking.

    The lump in the throat I have'nt experienced though I do have trouble sometimes in swallowing food - never use to before I was diagnosed.

    I suspect what Jack said is probably correct that it is the swelling of a small goitre, which will disappear as you take in more thyroxin. One of the first things that I notice when I am short of thyroxin is that my thyroid starts to swell and feels puffy.

    I still have not conquered this illness, really thought I could, but find it tough. Just when I feel I might be getting better, another sympton will suddenly appear ie bad pain in right hip :wah:

    Good to have a grumble. I think all of us hypo sufferers deserve to let off steam now and then. :steam: Larks.


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