Hi all , I posted on here a short while ago as my tsh levels were over 4 and my doctor wouldn't budge on upping my levothyroxine dose , anyway after a bit of a battle they've agreed to give me a blood test as they wont accept the private one I had done......my blood test isn't till 1.30 in the afternoon which I knows not idea as mornings better for bloods but do I take my levothyroxine before I go ? And does it make a difference if I eat and drink that day before my test?
Thanks
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Pixibell
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As your TSH was high in range and your GP reluctant to increase your dose, then your next test is unlikely to give you the result you are looking for. When looking for an increase in dose it's vital to get the highest TSH as possible and by having your test at 1.30pm your TSH will be at it's lowest point of the day, see first graph here:
You really should try and get an early morning appointment and have nothing other than water before the blood draw.
Taking Levo before the test will give a high FT4, it wont affect TSH.
Always advised here, when having thyroid tests:
* Blood draw no later than 9am. This is because TSH is highest early morning and lowers throughout the day. If looking for a diagnosis of hypothyroidism, an increase in dose of Levo or to avoid a reduction then we need the highest possible TSH
* Nothing to eat or drink except water before the blood draw. This is because eating can lower TSH and coffee can affect TSH.
* Last dose of Levo 24 hours before the test, take that day's dose after the blood draw. This is because if you take your Levo before the blood draw the test will measure the dose just taken and show a false high. If you leave longer than 24 hours the result will show a false low.
* 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.
Thanks sea side susie , I did try to get am am appointment but they wouldn't budge on it .....so I'll have to stick to 1.30 unfortunately but I'll take your other advice on board
Though the idea of eating nothing before testing in the morning may seem odd, it is a way of always making the test situation the same on every occasion you have it. Otherwise, eating various foods before could affect the results differently owing to interfering with T4 you take . You needn't fast more than not having anything to eat after a light supper the night before and don't eat before the morning test. Liquids are usually no problem.
I don't agree with a need to fast, other than avoid large fatty meals, before a thyroid blood test. Certainly there is no problem in eating and drinking the day before a blood test.
Your TSH will be at its lowest after midday. Another consideration not appreciated by doctors is that TSH varies considerably during the menstrual cycle frontiersin.org/articles/10... . Perhaps you could arrange the blood test on an appropriate date.
The NICE guidelines state: -
1.3.6 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.
This is considerably more than the 25 mcg you are prescribed. They also say the dose should be adjusted to resolve symptoms: -
1.4.1 Aim to maintain TSH levels within the reference range when treating primary hypothyroidism with levothyroxine. If symptoms persist, consider adjusting the dose of levothyroxine further to achieve optimal wellbeing, but avoid using doses that cause TSH suppression or thyrotoxicosis.
So your GP should consider the guidance.
Another issue addressed in your other post is that you are planning pregnancy so your TSH should be kept below 2.5 in any case (or lower).
Many doctors don't do maths. so they fail to appreciate that TSH responds exponentially to falling hormone levels, this means a change in TSH from 4.0 to 2.0 is of much greater significane than from 6.0 to 4.0.
Thank you for that info from the nice guidelines , I did print some other stuff off myself from nice about pregnancy and conception which another member on here helpfully provided and posted it in to my gp but they disregarded it! I'm not happy about it so this blood test is my last shot with them to get them to alter my levothyroxine dose to get my tsh down to 2.5 or below ....I didn't know that levels alter throughout the day so are you also saying a morning blood test is preferable ? ....if my go wont help me after my bloods then I dont know where I go from there 😒
You can see how TSH varies here academic.oup.com/view-large... . Note that the Y-axis numbers don't start at zero so the picture exaggerates the variations. Nonetheless TSH varied between 1.4 and 2.3 on average for the people in the trial. These are average figures, some people will vary more and some less.
Theses results are for people not taking thyroid hormones. The graphs may be different for patients on levothyroxine and more so for anyone taking liothyronine or NDT. As you are on only 25 mcg levothyroxine it will have little effect on your results.
I basically need my tsh to be as high as possible at the time of test realy , or there just going to fob me off and I'm worried they'll show up as just over 4 and my gp will say there fone which obviously there not
Don't have a blood test in the afternoon, you TSH will be lower than at 9 am, and they'll be able to say 'you're fine, we've tested , go away '
i've just waited 5 weeks for a blood test at the time i wanted..... to book it i had to stand at reception for several minutes while they said "there are none ,we don't do them, everythings booked, we only get a few allocated each day , can you phone tomorrow etc, etc, etc.
I just said 'i don't have enough phone credit to wait in phone queues, and i cannot get to an appointment after x o clock because of my work , i don't mind if i have to wait a few weeks for an appointment".... if you stand there long enough and keep smiling they will find you one at the time you want,,, eventually.
Thank you tatty bogle ...seems like I'll have to be more politely assertive to get an am appointment then as per everyone's advice on here and thank you for the extra link
thyroid disease comes with an unexpected gift....free lifelong course of Assertiveness training (whether you want it or not )
You don't have to be pig headed to get thyroid disease treated...... but it helps. I smile at the receptionist's and they smile at me, but i don't think that's what either of us are really thinking.
I'm only on 25mc hence my tsh being over 4 , I'm currently also taking a prenatal multivitamin vitamin which includes vit d , b12, folic acid ( is that the same as folate 🤔? I have no idea about hashimoto's, I was just told several years ago my tsh was borderline and been on the 25mc ever since ...its only now my ivf consultant has advised my levothyroxine needs altering and at over 4 my tsh is to high for conception and pregnancy ...... but I'm stuck in this battle with my gp practice who refuse to budge on changing my dosage ,
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