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Advice please on latest test result and what is usual dose of levothyroxine

Good morning everyone,

I would please like some advice before my next GP appointment as I think I probably need an increase in my Levothyroxine. I was diagnosed with Hashimoto's in August and started on just 25mcg of Levo. It was only increased to 50mcg in October going by a blood test. I am still feeling very ill I constantly have a cold and sore throat that never seems to go away. My latest result from a week ago is below:

Serum free T4 level 19.2 pmol/L [9 - 19]

Serum TSH level 1.64 miu/L [0.35 - 4.94]

I'm just wondering how to prepare for the doctors appointment and should I be insisting on an increase in the Levo now. Also is 100mcg the usual dose you should aim for to feel better on. I do realise everyone is different.

Please could I have some advice on the above please. Thank you.

11 Replies

The levels suggest that your dosage is not too far out. Your T4 level is above benchmark and TSH is sufficiently suppressed for the moment. Maybe get your T3 levels tested. Dosage can be anywhere from 25mcg to over 200 - it is based on your levels, 100 mcg would seem too high based on these tests. Do you have your results before you started treatment?


I doubt you'll get an increase with those results. Your free T4 is at the very top of the range, and TSH is 'normal' so they'll be reluctant to push it up. What you really need is a free T3 result, to see if that is low, because you may not be converting properly. You don't want to take more Levo if that's the case, you'll end up with formation of reverse T3 and that's not good.

There is no golden dose to aim at, unfortunately, as we are all different.

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Thank you both for your replies my test result at diagnosis was :


FREE THYROXINE *11.5 pmol/L 12.00 -22.00

TOTAL THYROXINE(T4) 62.2 nmol/L 59.00 -154.00

FREE T3 4.44 pmol/L 3.10 -6.80

Thyroid AntibodiesTHYROGLOBULIN ANTIBODY 80.900 IU/mL 0.00 -115.00


This was in July and since then my test in October was:

Serum free T4 level 13.2 pmol/L [9 - 19]

Serum TSH level 2.06 miu/L [0.35 - 4.94]

I can see my TSH level is coming down. Unfortunately I can't really afford to test the T3 myself at the moment and the GP doesn't do it.

Just wondering if I should ask to go up to 75mcg levo per day or do some people just stay on the 50 mcg for a while.

I know my antibodies have also risen since that test in July too. Any further advice would be appreciated. Thanks



Thyroid peroxidase and thyroglobulin antibodies are positive for autoimmune thyroid disease (Hashimoto's). There is no cure for Hashimoto's which causes 90% of hypothyroidism. Levothyroxine treatment is for the low thyroid levels it causes. Many people have found that 100% gluten-free diet is helpful in reducing Hashi flares, symptoms and eventually antibodies.



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Most people are adequately dosed when TSH is 1-2 with FT4 in the upper range. Some people do need FT4 over range to feel well and this will usually suppress TSH below range.

Read Treatment Options in thyroiduk.org.uk/tuk/about_... Email dionne.fulcher@thyroiduk.org if you would like a copy of the Pulse article to show your GP.

If your GP won't agreed to increase dose to 75mcg daily ask whether you can try 50mcg/75mcg alternate days.

Symptoms can lag behind good biochemistry by several months so it may just be a question of hanging in there on 50mcg.

Hypothyroid patients are often low/deficiency in ferritin, vitamin D, B12 and folate so it is worth asking your GP to test. Symptoms can be very similar to hypothyroid symptoms.

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Hi Clutter ,

Thank you very much for your reply too. I have been cutting gluten from my diet but not sure that I have noticed any difference with that yet.

I will ask for an increase up to the 75mcg and see what the GP says. I will also bring the Pulse article in case it is needed. I'll also read those treatment options so I can go prepared. Thank you for all that information.

I do also have PA and have recently just started on B12 treatment again so yes probably a lot of my symptoms are probably caused by that. Also like you say my ferritin levels have also been really low. I do have Gentle Iron 20mg I'm just not sure if it would be safe to take this everyday? Would you be able to advise on this please.

Thank you everyone for your helpful replies



You should have B12 injections every 3 months if you have pernicious anaemia. healthunlocked.com/pasoc are the experts on PA and B12 deficiency.

If ferritin is very low you need more than Gentle Iron. Try Ferrous Fumarate 210mg daily taken with 1,000mg vitamin C to aid absorption and minimise constipation. Iron must be taken 4 hours away from Levothyroxine.

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Hi again Clutter,

I have been also posting on the PA forum and have just recently had my B12 injections reinstated after a long struggle with the current GP practice. So hopefully they will start to have an effect soon.

I only had my ferritin tested in July also privately and that result was:

FERRITIN 46.6 ug/L 13.00 -150.00

The GP just told me this was normal. I had iron deficiency anaemia in March which was very severe. I stopped taking any iron a couple of months ago as was a bit worried about taking it long term. I do still have some of the Ferrous Fumarate left. Should I start back on them like you advise. Sorry for all the questions I do get confused easily.

Thank you for your time in reading and replying.



Ferritin 46 is 'normal' because it is in range. 13 and 150 are both normal too but half way through range 75 - 100 is usually optimal.

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Essential to have good levels of vitamin D, folate, B12 and ferritin.

Low vitamin levels stop Thyroid hormone working

Your FT4 is right at top of range. Increasing dose yet is probably not a good idea.

Getting vitamins to good levels is essential

All thyroid tests should be done as early as possible in morning and fasting and don't take Levo in the 24 hours prior to test, delay and take straight after. This gives highest TSH, lowest FT4 and most consistent results

Poor gut function can lead leaky gut (literally holes in gut wall) this can cause food intolerances. Most common by far is gluten

According to Izabella Wentz the Thyroid Pharmacist approx 5% with Hashimoto's are coeliac, but over 80% find gluten free diet helps significantly. Either due to direct gluten intolerance (no test available) or due to leaky gut and gluten causing molecular mimicry (see Amy Myers link)

But don't be surprised that GP or endo never mention gut, gluten or low vitamins. Hashimoto's is very poorly understood

Changing to a strictly gluten free diet may help reduce symptoms, help gut heal and slowly lower TPO antibodies. It does need to be 100%







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Hi Clutter,

Thank you for your advice about the ferritin. It looks like I need to get the level up a bit. I did find the ferrous furmanate tablets a bit harsh on my stomach. Would you be able to advise how many of the Solgar Gentle Iron I would need to take to be roughly equivalent to the 210mg of the other tablets.

Maybe the 50mcg is ok for the time being of Levothyroxine then. Thank you for that advice.

Hi SlowDragon. Thank you for your reply too. I have been trying really hard with going gluten free. But I do slip up especially when eating out with family.

A lot of my vitamins probably are low too. My Vitamin D level was very low in March too so should probably be supplementing it every day for the winter now.

I'm now not sure if I have been delaying taking the Levo for long enough before the blood test. I usually take it at night. So if I dont take it the night before and usually have the blood test at 8.30am is that enough time. I do always have a fasting blood test.

I will read all the links you have provided. Thank you so much for helping me.

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