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Hey, just after some advice about my upcoming blood test please.
Do I withhold my meds beforehand, then take them after 9am blood draw.
New endo says don't withhold, take as normal.
But I've read that isn't the correct way, and won't give accurate results.
Tests are for levothyroxine, growth hormone, hydrocortisone, and testogel.
Plus b vits, ferritin etc.
When booking thyroid tests, we advise:
* Book the first appointment of the morning. This is because TSH is highest early morning and lowers throughout the day. 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.
* Fast overnight - 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. Eating may lower TSH, caffeine containing drinks affect TSH.
* Leave off Levo for 24 hours before blood draw, if taking NDT or T3 then leave that off for 8-12 hours. Take 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.
These are patient to patient tips which we don't discuss with doctors or phlebotomists.
One of our member's endo agrees with the timing of Levo and T3 before blood draw.
If you take Biotin, or a B Complex or any other supplement containing Biotin, leave it off for 7 days before the test, taking Biotin can give false results for any blood test.
If you take iron tablets, leave off for a week before the test, also don't eat liver or other high iron foods during that time.
Thank you for your reply.
I need to be armed with info, to hit endo with when I next see her, and it's got to be watertight, as she has specifically asked me to not withhold meds.
I've booked for 9am. 😊
It depends what test result is important. Most doctors tend to adjust dose by TSH level. Taking your thyroid meds before the test won't affect TSH level. Time of test, eating and caffeine containing drinks affect TSH.
If you take your thyroid hormone replacement too close to the blood test, the FT4 result will show the dose just taken and give a false high result. Levels of FT4 peak two hours after you take Levo, same with FT3 result when taking NDT or T3, about 2.5 hours. Take them too far away from blood draw, you get false low results.
So if you want to know normal circulating hormone level then the timing suggested above is what will give that. The trouble is getting that through to doctors.
I take my levo at nite time, as I read that's better for absorbtion and also don't have to worry about avoiding anything at breakfast.
I'll take my levo 24 hours before test tho, and I'll probably tell her that I took at the normal time I usually take it.
Im assuming that I withhold my morning hydrocortisone too, for the same reasons as above?
And growth hormone and testosterone gel too?
Sorry, I have no idea about your other medications, I have no experience of them.
Ok, thanks for your advice on levothyroxine. 😊
Yes, I would do what Seaside Susie advises and fib. The last thing we need is to give endos any excuse for lowering the dose if we don’t feel over medicated. They can be obsessed with blood results and ranges rather than symptoms to the detriment of the patient. 🤸🏿♀️🥛
Oh, yes they're obsessed with blood test results alright.
My GP rarely looks round from his computer screen at me when I go to see him. I know I’m no oil painting to view, but I could be a rotting corpse in the chair opposite and he’d tell me my blood results said there was nothing wrong as everything was in range. 💀🤸🏿♀️🥛
My main issue with seeing endocrinologists, is that all they appear to be concerned about is that I'm alive, and upright.
Quality of life seems to be quite far down their list of priorities.
It's very frustrating.
It is - very. My GP told me I was okay as my results were ‘coming down and nearly in range now’ - if I had had the energy I would’ve laughed. I looked like a tramp - I couldn’t even be bothered to iron my clothes anymore, my hair was like straw and my complexion a fetching shade of grey. I shuffled in to see him and barely had the energy to speak. So of course - I was fine! That was the moment I had to push the nuclear button and do something I hate - go private. But there was no way I was going to get well without paying for the privilege. It’s heart-wrenching to me that so many on here don’t have that option and remain ill due to intransigence. 🤸🏿♀️🥛
Yes it is terrible that a lot of Dr's are either next to useless or have a god complex.
I was misdiagnosed for many years with depression, when I had hypopituitarism.
I remember telling them, that I wasn't depressed. Next Dr I see looks at my records, and says, 'youre depressed'!
I got diagnosed by a McTimoney chiropractor, who I went to see, with a bad back.
Im lucky to be alive.
So, I don't trust any Dr's, they've got to earn my trust, and very few of them have done that!
And going private has worked for you?
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