I have been on 50 levothyroxine for around a year as my blood readings showed subclinical hypothyroid around 5 TSH. This reduced the TSH to 1.9 without side effects but my latest reading was 4.44 and I was tired again so they upped to 75 8 weeks ago. My periods have never been irregular and I have a 22 day cycle. Last month I was a week late which is very unusual for me and I have now started spotting midway through a cycle. Has anyone else experienced menstrual changes in levothyroxine? Could this mean the dose is too high?
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Mrs_Tumnus
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more likely dose will need further increase after next blood test
50mcg is only the standard STARTER dose
You shouldn’t have been left on only 50mcg that long
Even if we frequently start on only 50mcg, most people need to increase levothyroxine dose slowly upwards in 25mcg steps (retesting 6-8 weeks after each increase) until eventually on, or near full replacement dose
In the majority of patients 50-100 μg thyroxine can be used as the starting dose. Alterations in dose are achieved by using 25-50 μg increments and adequacy of the new dose can be confirmed by repeat measurement of TSH after 2-3 months.
The majority of patients will be clinically euthyroid with a ‘normal’ TSH and having thyroxine replacement in the range 75-150 μg/day (1.6ug/Kg on average).
The recommended approach is to titrate thyroxine therapy against the TSH concentration whilst assessing clinical well-being. The target is a serum TSH within the reference range.
……The primary target of thyroxine replacement therapy is to make the patient feel well and to achieve a serum TSH that is within the reference range. The corresponding FT4 will be within or slightly above its reference range.
The minimum period to achieve stable concentrations after a change in dose of thyroxine is two months and thyroid function tests should not normally be requested before this period has elapsed.
which brand of levothyroxine was 50mcg
Which brand are you taking now
Bloods should be retested 6-8 weeks after each dose change or brand change in levothyroxine
For full Thyroid evaluation you need TSH, FT4 and FT3 tested
Also both TPO and TG thyroid antibodies tested at least once
Very important to test vitamin D, folate, ferritin and B12 at least once year minimum
When were vitamins last tested
What vitamin supplements are you taking
About 90% of primary hypothyroidism is autoimmune thyroid disease, usually diagnosed by high thyroid antibodies
Autoimmune thyroid disease with goitre is Hashimoto’s
Autoimmune thyroid disease without goitre is Ord’s thyroiditis.
Both are autoimmune and generally called Hashimoto’s.
Low vitamin levels are extremely common when hypothyroid, especially with autoimmune thyroid disease
20% of autoimmune thyroid patients never have high thyroid antibodies and ultrasound scan of thyroid can get diagnosis
In U.K. medics hardly ever refer to autoimmune thyroid disease as Hashimoto’s (or Ord’s thyroiditis)
Recommended that all thyroid blood tests early morning, ideally just before 9am, only drink water between waking and test and last dose levothyroxine 24 hours before test
This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip)
Private tests are available as NHS currently rarely tests Ft3 or all relevant vitamins
Testing options and includes money off codes for private testing
At my most recent test after a year on 50mcg, my Serum free T4 level was 12.2 pmol/L (7.0 - 17.0) and TSH 4.44. This is when they increased to 75mcg around 8 weeks ago. I have another test on Jan 2nd. Now that I have irregular bleeding, I am concerned this is a sign that the increase in dose is too high as I haven't ever experienced this before.
If symptoms of hypothyroidism persist despite normalisation of TSH, the dose of levothyroxine can be titrated further to place the TSH in the lower part of the reference range or even slightly below (i.e., TSH: 0.1–2.0 mU/L), but avoiding TSH < 0.1 mU/L. Use of alternate day dosing of different levothyroxine strengths may be needed to achieve this (e.g., 100 mcg for 4 days; 125 mcg for 3 days weekly).
Many, many thyroid patients will have TSH around or below one when adequately treated.
Most important results are always Ft3 followed by Ft4
And essential to maintain optimal vitamin D, folate, ferritin and B12
If symptoms of hypothyroidism persist despite normalisation of TSH, the dose of levothyroxine can be titrated further to place the TSH in the lower part of the reference range or even slightly below (i.e., TSH: 0.1–2.0 mU/L), but avoiding TSH < 0.1 mU/L. Use of alternate day dosing of different levothyroxine strengths may be needed to achieve this (e.g., 100 mcg for 4 days; 125 mcg for 3 days weekly).
Approximately how much do you weigh in kilo
guidelines on dose levothyroxine by weight
Even if we frequently start on only 50mcg, most people need to increase levothyroxine dose slowly upwards in 25mcg steps (retesting 6-8 weeks after each increase) until eventually on, or near full replacement dose
In the majority of patients 50-100 μg thyroxine can be used as the starting dose. Alterations in dose are achieved by using 25-50 μg increments and adequacy of the new dose can be confirmed by repeat measurement of TSH after 2-3 months.
The majority of patients will be clinically euthyroid with a ‘normal’ TSH and having thyroxine replacement in the range 75-150 μg/day (1.6ug/Kg on average).
The recommended approach is to titrate thyroxine therapy against the TSH concentration whilst assessing clinical well-being. The target is a serum TSH within the reference range.
……The primary target of thyroxine replacement therapy is to make the patient feel well and to achieve a serum TSH that is within the reference range. The corresponding FT4 will be within or slightly above its reference range.
The minimum period to achieve stable concentrations after a change in dose of thyroxine is two months and thyroid function tests should not normally be requested before this period has elapsed.
Consider starting levothyroxine at a dosage of 1.6 micrograms per kilogram of body weight per day (rounded to the nearest 25 micrograms) for adults under 65 with primary hypothyroidism and no history of cardiovascular disease.
Thank you so much for such a detailed response. Very helpful.
My test was done at 1pm - however, I work nights, so this test was done within an hour of waking.
Why do GPs insist on TSH being normal under 5? I have now seen a couple of doctors and they have both made me question my sanity over my symptoms. They believe my fatigue, weight gain and puffiness etc is not related to my thyroid as it has never been high enough to cause symptoms. 'Just a little high' is how they refer to it. If I wouldn't have found this website, I would have accepted defeat by now and given up on getting an answer to my symptoms. It might be worth noting that my ESR has been high since 2016. In 2016 it was 18 and it has remained high. My last test was 24. Just like with my thyroid results, the GP thinks this is acceptable?
Yes I had period problems..... Due to being under treated. Once on optimal treatment my periods returned to normal. It sounds like your GP doesn't really know much. Treating by the TSH alone is known to lead to under treatment...... You really need TSH, Ft4 & Ft3 doing to know how your thyroid hormone levels are responding. You can purchase these tests privately look on Thyroid UK website. I'm afraid I had to seek treatment advice elsewhere as my GP put me on 50mcg of levothyroxine when first diagnosed and left me for a whole year!! I felt shocking... However you need to be very careful who you see......as many are diabetes specialists not thyroid.
Yes, Levothyroxine causes menstrual irregularities particularly after changes of dose. It can take a while before it settles in a new or previous norm.
By the way, a 22 day cycle is quite short. So, I would not be surprised when on the right dose your cycle could be longer.
my periods completely stopped for nearly a year. Went to dr and they nearly had me on HRT for early menopause at 37, despite several blood tests showing subclinical and reporting symptoms. My periods have returned since starting thyroxine.
Most unlikely to be over medicated on 75mcg. It’s just a result of hormonal upset and should settle.
You say you are due a blood test on 2nd Jan. it’s most important that you prepare ahead for that. The last dose of Levothyroxine should be taken 24hrs before the blood draw. If you take your medication when you get up that’s easy. If you take it at bedtime or some other part of the day then you need to adjust the time you take it 2 days before so that you leave that 24hr gap. If you don’t do this, your blood test could show a false high and your GP will keep you under medicated.
On test day make sure you book first thing in the morning. By 9am. Our body works in circadian rhythms and we need the blood test when the TSH cycle is as high as we can capture to ensure we get the best treatment. If your test is already booked for later in the day ring up and ask to move it to the next available early morning appointment. This is important. Don’t be fobbed off and don’t fob yourself off either.
On the day don’t take your daily dose until the blood test is done. I have mine plus water in the car waiting for me. Drink nothing but water up until the test and don’t eat either. This will give you the best test results possible to work with.
If you take any supplements that contain Biotin you need to not take that for several days leading up to the tests. It can affect the test result.
Come back with your new results and let’s see where you are on your treatment path.
Thank you so much for your responses. My GP seems to think that my readings are subclinical and I would be fine without any medication at all. I am very confused as to what is classed as hypo. Even on 50 my results are 4.44 and I'm puffy, fatigued etc.
Unfortunately, GPs have very little training on the thyroid gland and many aren’t especially good at treating hypothyroidism appropriately. “Subclinical” should mean you aren’t experiencing symptoms; unfortunately, many GPs think it’s all about whether your test results fall into a laboratory reference range (which many of us believe to be far too wide).
You almost certainly need a raise in levothyroxine. Most people who take levo tend to feel best when their TSH falls below 1.0 and their FT4 is in the upper part of the reference range.
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