I was wondering if being on a high dose of Levothyroxine could give you symptons of Hyperthyroidism?
Back in August 21 not fully undestanding the TSH test range I asked my doctor if I could increase my dosage from 150mg Levothyroxine to 175mg thinking that a result of 0.99 mu/L (0.34 - 5.6) was low !
Because of Covid I didn't get retested until July 22 0.20 mu/L (0.34 - 5.6)
Obviously doctor asked me to reduce dose back to 150mg which when tested October 22 resulted in 0.84 muL (0.34 - 5.6).
I'm piling on the weight after losing 2 stones over the last couple of years and just starting to look at everything to try and sort that out.
Thanks
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Dadof5
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I don't know how much you have read here or what your understanding of thyroid tests are but it might be helpful to explain.
Back in August 21 not fully undestanding the TSH test range I asked my doctor if I could increase my dosage from 150mg Levothyroxine to 175mg thinking that a result of 0.99 mu/L (0.34 - 5.6) was low !
The aim of a treated hypo patient on Levothyroxine is to lower TSH. Hypothyroidism is diagnosed when TSH is high - the thyroid stops producing enough thyroid hormone, the pituitary detects this and sends a signal to the thyroid to produce more, that signal is TSH - Thyroid Stimulating Hormone. When the thyroid can't produce enough (hypothyroidism) then we take Levo to replace what we can't make ourselves, and the aim is to lower TSH.
Although TSH is useful for diagnosis, once on Levo it doesn't have much purpose, the important things to test are the actual thyroid hormones - FT4 and FT3 and it's these tests that tell us if we are adequately replaced with synthetic thyroid hormone (FT3 being the most important test) but unfortunately doctors aren't taught this, they think the only indicator is TSH.
I'm piling on the weight after losing 2 stones over the last couple of years and just starting to look at everything to try and sort that out.
Weight increase can be an indication that you are undermedicated so you need a full thyroid function test that includes TSH, FT4 and FT3. It's often impossible to get full testing with a GP, even when a GP requests it the lab can override the request if TSH is within range, so many members here resort to private testing with one of our recommended labs.
Most hypo patients feel best when TSH is 1 or below with FT4 and FT3 in the upper part of their reference ranges. This is not set in stone as we are all different but it's a helpful guide.
How much Levo do you take?
Do you do your thyroid tests as we always advise:
* Book the first appointment of the morning, or with private tests at home no later than 9am. This is because TSH is highest early morning and lowers throughout the day.
In fact, 9am is the perfect time, see first graph here, it shows TSH is highest around midnight - 4am (when we can't get a blood draw), then lowers, next high is at 9am then lowers before it starts it's climb again about 9pm:
If we are looking for a diagnosis of hypothyroidism, or looking for an increase in dose or to avoid a reduction then we need TSH to be as high as possible.
* Nothing to eat or drink except water before the test - have your evening meal/supper as normal the night before but delay breakfast on the day of the test and drink water only until after the blood draw. Certain foods may lower TSH, caffeine containing drinks affect TSH.
* If taking thyroid hormone replacement, last dose of Levo should be 24 hours before blood draw. If taking NDT or T3 then last dose should be 8-12 hours before blood draw, split dose and adjust timing the day before if necessary. This avoids measuring hormone levels at their peak after ingestion of hormone replacement. Take your thyroid meds after the blood draw. Taking your dose too close to the blood draw will give false high results, leaving any longer gap will give false low results.
* If you take Biotin or a B Complex containing Biotin (B7), leave this off for 7 days before any blood test. This is because if Biotin is used in the testing procedure it can give false results (most labs use biotin).
These are patient to patient tips which we don't discuss with phlebotomists or doctors.
Also, do you take your Levo on an empty stomach, one hour before or two hours after food, with a glass of water only, no tea, coffee, milk, etc, and water only for an hour either side, otherwise absorption will be affected. Do you take any other medication and supplements 2 hours away from Levo (some need 4 hours)?
Are your key nutrients optimal? This is important for any thyroid hormone to work. We suggest testing
Vit D
B12
Folate
Ferritin
If you have had any of these tests done please post the results, along with their reference ranges (ranges are important as they vary from lab to lab) so that we can comment.
If you've not had them all done you could ask your GP if he's willing to do them, if not then it would be worth considering whether you can stretch to testing yourself.
Basic thyroid function test is cheapest with Monitor My Health which is an NHS lab at Exeter hospital, this particular lab may be more acceptable when discussing results with a GP. The Thyroid Test or Advanced Thyroid Test would be appropriate. If you want to include vitamins as well then consider their Full Health Screen. Details and discount code here:
Hi Dadof5 .yes too high a dose of levo (overmedication) can certainly give symptoms of HYPERthyroidism, as the cause of 'overmedication' and 'hyperthyroidism' is effectively the same thing .. "too much thyroid hormone".
It's just that in 'true' hyperthyroidism ,the excess T4/T3 is coming from your own thyroid gland going nuts , but in overmedication , you are taking too much T4 which also makes your T3* go up. ( *edited to correct typo)
But the best way to tell if the dose you take is actually 'too much' , is NOT just looking at the TSH .
TSH is fairly useful for diagnosis , but it can be a bit misleading for finding the right dose . To know the right dose you/ your GP need to take into account not just the TSH but also the fT4 levels AND the symptoms ... and preferably the fT3 too ... (but you usually have to test fT3 yourself ass the NHS usually won't).
So how did you actually feel on 175mcg ? better or worse than 150mcg ?
and do you have any other results ie fT4 ?
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To clear some things up just in case you are still confused.
TSH Thyroid Stimulating Hormone is not a thyroid hormone . it's just a message to ask the thyroid to make more/ or less of the actual thyroid hormones ( T4 / T3)
Low TSH indicates High (T4 / T3) ( hyper / overmedicated ).. so the response to a "far too low TSH" is usually a dose decrease ... not an increase. However as mentioned above this does not just depend on the TSH. you need to know the full picture .
High TSH indicates Low T4/T3 levels (hypo) ... so the response to a high TSH is usually a dose increase.
Helps to keep it clear in your head if you think of TSH and T4/T3 sitting on opposite ends of a see-saw:
I haven't had my T4 tested since 2016, which is around the time I moved and changed doctors surgery. My new doctors have been more concerned with my pre diabeties if i'm honest.
My last T4 which was in October 2016
T4 9.5 pmol/L (7.5 - 21.1).
I am looking at getting one of the private test, recommended on here done once I can afford it and will do the test as advised on here.
To be honest on the higher dose I didn't really notice any major change I how I felt apart from my upper arms used to ache but I don't know if that was because of the doseage or because I needed new pillows!
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