Thyroid UK

Gp started me on 25mg Levo, do I have to wait 6 weeks before retest

I started taking 25mg Levo on 21st December, so only 2 weeks ago. I am feeling worse than I was. Do I really have to cope like this for another 4 weeks?

Results I have been given:

TSH normal range 0.27 - 4.20

My TSH results:

20/7/17 - 6.25

22/8/17 - 4.22

15/12/17 - 4.65

Free T4 normal range 10.50 - 22.00

My results

20/07/17 12.6

22/8/17 12.9

Tested on 22/8/17

Anti TPO 74 [high]

IgA anti tTG <1

Anti ENA 0.2

Anti nuclear Antibodies NEG

On the standard blood tests for 20/7/17 Iron was listed as 31 - high

I had results from 4 years ago for vit b12 (446), folate (15.9) and ferritin (26.5), levels all within normal lab limits at that time, but not tested since.

I have no idea why the GP chose to start me on 25mg, other than that my levels are all close to the normal range!!! I feel like I really should not feel as bad as I do considering the levels I have.

5 Replies

Dr Toft thinks that 25 ug starting dose can actually worsen symptoms, and he goes straight in at 50. Toft is a former president of the RCP and has a private practice at the Swire in Edinburgh.

1 like

Adding to what diogenes wrote, 25mcg is a starting dose for the very old, the very young, or people with a heart condition; and presumably GPs either have forgotten this, or are too inexperienced to understand, when they prescribe such a low dose for patients outside of these at risk groups. Having said that, levothyroxine has a long half life and its effect is generally a slow burn rather than immediate .... So "normally" you would have a new blood test and dose increase as necessary, 6 weeks after the previous one otherwise you won't have a true picture of how that first dose is benefitting you. But given that it's probably a sure fire certainty that 25mcg is nowhere near what will be your optimum/euthyroid dose, it's up to you if you want to ask for a further 25mcg dose increase now, in expectation of that, and then have your next blood test 6 weeks after that. In support of that, you could refer your Dr to the instructions in the Patient Information Leaflet (PIL):


The usual starting dose is 50-100 micrograms every day. Your doctor may increase the dose you take every 3-4 weeks by 50 micrograms until your thyroxine levels are correct. Your final daily dose may be up to 100-200 micrograms daily.

Patients over 50 years of age:

The usual starting dose will be no more than 50 micrograms every day. The dose may then be increased by 50 micrograms every 3-4 weeks until your thyroxine levels are correct. Your final daily dose will be between 50-200 micrograms daily.

Patients over 50 years with heart problems:

The starting dose will be 25 micrograms every day or 50 micrograms every other day. The dose may be increased by 25 micrograms every 4 weeks until your thyroxine levels are correct. Your final daily dose will usually be between 50-200 micrograms daily.


Standard starter dose is 50mcg

Your antibodies are high this is Hashimoto's, (also known by medics here in UK more commonly as autoimmune thyroid disease).

About 90% of all hypothyroidism in Uk is due to Hashimoto's

Essential to test vitamin D, folate, ferritin and B12.

Always get actual results and ranges. Post results when you have them, members can advise

Hashimoto's affects the gut and leads to low stomach acid and then low vitamin levels

Low vitamin levels affect Thyroid hormone working

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

Ask GP for coeliac blood test first


A low dose can make us feel worse and the starting dose is 50mcg usually, but many doctors haven't a clue of how bring their hypo patients to good health. He probably thought as your TSH was just over the range that 25mcg was sufficient. He is wrong.

We have to read and learn by asking questions on the forum and before long we know our body best and how it feels on differing doses of thyroid hormones or options apart from levothyroxine.

We should have a blood test after six weeks and they should always be at the very earliest possible, fasting and allow a 24 hour gap between last dose of levo and blood test. Levo should be taken on a fasting stomach (usually when we get up) with one full glass of water and wait an hour approx before eating.

When you state results you always have to put the ranges - labs differ - and it makes it easier to respond.


Thank you for your replies. My GP is very old school, patient should not use internet to diagnose and decide on treatment, they believe this is the roll of the doctor and any attempts to overtly correct is abruptly halted. I have to gently suggest changes.

So I fear that I will have a problem if my next results come just inside the ‘normal’ range. I need to find information that I can subtly hand on.

Feeling worse - will this be reflected in the blood test results do you think?


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