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Thyroid UK
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Blood Tests

Hi Everyone - I was just wondering if any recently diagnosed people could help out. My doctor has given me 8 weeks of tablets and told me to book a blood test for later than 8 weeks (I've booked mine for 9 weeks time).

At the time I didn't think to ask (shocked by the diagnosis) but this will mean that at my blood test I'll have been off Levothyroxine for a week, and 2 weeks before I get an appointment scheduled to talk again with the doctor and get a new prescription.

Does this sound like normal practice? Is it so they can see whether my results were a one off low?


(FYI: 15.22 TSH (0.27-4.2); 6.8 T4 (12-22))

10 Replies


Ask your GP receptionist what the procedure is for ordering a repeat prescription and how much notice the practice requires to process the prescription. You should probably order a repeat at least a week prior to your tablets running out.

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Yes perhaps that's what she assumed I'd do. Probably best to try and get a repeat rather than letting it lie until the appointment


Are you sure he didn't say NOT more than 8 weeks? Normally, it should be between 6 and 8 weeks for a retest.


Yeah she specifically said more than because I double checked my calendar in the appointment. Think she wanted at least 8 weeks for the hormones to do their job, given the high level of my imbalance


Well, they're not drugs. Levo is thyroid hormone. And staying on a starter dose for too long can be counter-productive. It just takes 6 weeks for the T4 (levo) to take full effect. It won't get any more effective after that, and your symptom will probably start coming back again.

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Suggest you move the test to 6 or 7 weeks and definitely make sure you get new prescription well before you run out (did GP tell you that all prescriptions are free for life when on thyroxine - you need to fill in a form I think - ask at surgery)

Important to stick to same brand of Levothyroxine - different brands are NOT interchangeable. Some brands really suit some people more than others. But if fine on the one you started on, make sure not to be given different one

Always take Levo on an empty stomach and nothing apart from water for an hour minimum after. No other medications at same time. Iron, HRT, vit D & few others must be at least fours hours apart from Levo.

Many of us take on waking, but others prefer bedtime. Perhaps just as more convienient, but some research suggests it may be more effective too.


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Thanks for the advice. I've filled out the form to get my free medicine certificate so hopefully will receive that soon.

I will check with my doctor in advance in case I was mistaken about the time to wait.

Currently I'm taking mine in the morning 1 hour before any food/drink (prescription only says 30 minutes). And the vit d and contraception at night time.

Thanks for the advice


Different brands can be interchangeable .I have noticed no difference . Accept that some folk need to stay with one brand.

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When I started on levothyroxine I was quite sure the makes would all be identical. Whilst I knew full well of others having issues, I felt that as I have no obvious food intolerances, etc., there would be no issues for me.

Having gone through the Teva scandal - where the tablets were most definitely NOT equivalent to other makes - I continued ignoring make.

In the end, I found they are different. I can tolerate all three. The all work up to a point. But they feel a bit different. At on point I was trying one Actavis and one Mercury Pharma 50 microgram tablet to see if the differences would "cancel each other out".

Ended up on Actavis and a small dose of Uni-Pharma.


Update. I called the doctor and she confirmed that she wants the re test after 8 weeks but she is writing up my repeat prescription that will more than cover the gap in between - so I'll be staying on 100mcg for now

Clearly everyone has different experiences and doctors, I just thought it might help to compare!


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