Latest bloods: Hi so bloods taken last Friday... - Thyroid UK

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Latest bloods


Hi so bloods taken last Friday (thyroxin 37.5)

Bit confusing...I'm guessing the tsh will go down..

Tsh 12.4 (0.27-4.5) it was 8 while on 25mcg levo

Ft4 23.7 (11-23)

Ft3 4.85 (3.1-6.8)

B12 473 (197-771)

Folate >20 (2.0-18.7)

Ferritin 39.0 (20-130) it isn't really going say I've been taking ferrous fumerate for a while!

Hoping tsh will come's been 3/4 weeks since going from 25mcg levo to 37.5


35 Replies

Goodness me! Why such a stupidly small increase in dose? Do you have a heart condition? Normally the starting dose is 50 mcg and increases 25 mcg every six weeks. That increase is not likely to make a dent in that TSH. But why did you test after only 3/4 weeks? Normally one leaves six weeks.

However, your FT4 is unusually high for such a small dose. Did you take your levo on the morning of the test?

I usually take it at 6am, but I left it till half 8, test for 9..I felt rubbish so I took it. I have been getting tachycardia and now am on beta blockers...their issue was my ft4 was on the higher end, so they're reluctant to give me a decent dose. But my tsh has gone up..what's that about? Gonna redo it in a month. I was told that long, so that's what I did. Another GP said I might be running high..which is what I've thought for a while..even when I had a tsh of 26, ft4 wasn't low.

OK So that explains the incredibly high FT4! Did you not know to leave 24 hours between your last dose of levo and the blood draw? Even if you felt rotten, taking your dose of levo won't make you feel better, because it's slow-acting - like six weeks.

I would imagine that your TSH is high because your real FT4 is very low. Taking your levo an hour before the blood draw would just measure the dose you just took, rather than what is normally circulating in your blood. So, those labs are actually nul and void. Except for the FT3, it wouldn't have affected that. And that isn't too bad - it's mid-range. But probably better higher.

I should imagine you need an increase in dose, but I can understand your doctor's reluctance to give it. You'll probably have to wait until next test and then leave the 24 hours' gap before the test to get a true FT4 level. So, that's what you've always done? Only left 1 hour between the last dose and the blood draw? And that's why you're on such a silly little dose? Never listen to doctors, always ask here. :)

Hi, thanks..I will do this next time! Definitely! So 24 hours? I'm confused; wouldn't you want to measure what is in your blood, the combined levo and your own t4? Because, that's what you need to change and that's what will be in your blood normally, since you don't usually have a 24 hour break? Sorry..if that doesn't make sense!

in reply to Michaela_l

But when you take a levothyroxine tablet the T4 level in your blood spikes - typically around two hours after swallowing. Then tails off for several more hours.

There seems less sense in measuring the artifical spike level than the trough before your next dose is due. Aside from anything else, we are all different and the sharpness and timing of the spike is, effectively, unpredictable whereas a trough is pretty much obvious! :-)

in reply to helvella

Fair one.. :) I just thought an hour before wouldn't be enough time for it to do anything. Thanks

I second what helvella said.

A spike, by definition, is not permanent. It will only last a short time and then it will drop. And it's the measurement that is during the drop that is the normal circulating level. What you need to change is not the spike, it's the normal circulating level. I imagine you do leave 24 hours between each dose?

Even so, the sad fact is that if you continue to take your levo one hour before the blood draw, you will never get an increase in dose, because it will always be high, and will - probably - always be about the same level, because you're taking the same dose. You'd think doctor would notice there's something odd about that, especially when they look at the high TSH but, somehow, it just goes straight over their heads. So, good idea to leave the 24 hours, next time. :)

I will! Thank you! :D that helps a lot. Sorry, there's just so much going on with my health at the mo. I'm under cardiology, gastro, maybe being referred to neuro and obviously under endocrinology..but Ive asked to never see that consultant again!

Well, once you get your thyroid hormone levels up, you probably won't need cardiology, gastro or neuro anymore. Most of your problems will be solved by restoring your thyroid hormone levels. The problem with doctors - one of them - is that they don't know the difference between a symptom and a disease! :)

Hmm I know :( I imagine it is all from my thyroid..its just taken so long to get to this point. I've been made to feel like an idiot in many occasions. I'm starting to wonder if there's a link between working in the operating theatre and having thyroid many of my colleagues have had the same/similar issues.

Really? How strange. And yet your doctors still don't know anything about it! It's pathetic! But, the reason it's taken you so long is because your doctors don't know anything about it. You've got to stop them upping and downing your dose all the time. It's really not good for you. Dosing should be done by the FT3, that's the most important number. :)

Ahaha I try to explain that...they don't doesn't matter! Cardiology were really bothered about my thyroid..which is great! He was bothered about my ft3.

You'll probably find that most specialities know more about thyroid than the endocrinologist. Is he a diabetes specialist who thinks thyroid is a doddle?

My hospital call it the diabetes yes probably. I'm pretty sure I have adrenal fatigue too; he said it was fine, GP said yes there isn't much of a cortisol spike (short synacthen test), but he said it's not a good way of measuring it as I could have had elevated cortisol levels anyways from stress...either way..I'm not talking to endocrine any more.

I agree, it's not a good way to test for adrenal fatigue. You need a 24 hour saliva cortisol test, but you won't get it on the NHS.

Even if I pay for this...I doubt anything will be done about it. I'd like to know if this can be related to my random spikes of hypertension (Im hypertensive anyways, but more so) and tachycardia. Ive been looking at ways to support my adrenals anyway; don't most people with hypothyroidism have adrenal issues..

Not all of them, I don't think. I think it depends how long they've been undiagnosed. If they got diagnosed fairly quickly, then I think the adrenals are capable of bouncing back quite quickly.

Hypertension is more likely to be due to your low T3, I believe. It's a hypo symptom.

I've been hypertensive for years...I'm 26 now, I'd say the last 4 years maybe. I believe I've had hypothyroidism for years..I started collapsing etc when I was a student after around a year of working in the operating theatre. I had raised tsh, which then went back down..but I never found how it might have been, in reality, still quite high. I have an inverted t wave and abnormal st segment on ecg..had that for a while..which again indicates I've probably had it for a while..long enough for that!

Yes, you probably have been hypo for a long time. More routine testing ought to be done on the thyroid to pick it up early. But, in reality, they don't want to pick it up at all!

I get that feeling, yes. I also mentioned that I've been put on beta blockers and the fact they are used to treat hyperthyroid patients...I've read an awful lot that this is because it helps inhibit the conversion of t4 to t3..but a GP today said no, it only relieves the symptoms of hyperthyroidism.....hmm..

Anyways...I shall go back in a month, and not take my levo until after the test. In the mean time, I'm trying (finding it hard) to cut out gluten, I'm gonna buy a water filter to cut down the amount of chlorine and fluoride i'm consuming...and help my body make as much t3 as possible; I have a list of things which will help.

Thank you

It's not all beta blockers that stop conversion. But, yes, that is one of the reasons they put hypers on them, that and because they often have heart problems with the high fT3. But, I wouldn't expect a GP to know that.

It's usually Hashi's people that find it helpful to go gluten-free, because they are very often gluten-sensitive. I don't think it's going to help your thyroid in any way. But, worth a try, I guess, if you can do it. But, to help, it has to be 100%.

No doctor has said I have 'hashimotos', but given I was positive for tpo antibodies and with one GP saying there's a lot of autoimmune issues going on... I'd say I am.

I probably have a bit of leaky gut; previous bowel resection and bloat an awful lot! I'm trying to help any way I can. I read a piece by a woman who reversed her hashis, that would be amazing...but..let's be honest, it's not gonna happen.

On a side note; I wonder if it's my exposure to betadine iodine and x-rays (there's usually not enough neck guards to go around) which could be causing issues, not just myself but others working in theatre...just an idea...never looked at any research, or if any exists.

OK, so you have Hashi's.

I don't know about x-rays - I think they affect the thyroid itself, not the immune system. But certainly excess exposure to iodine can trigger Hashi's.

Could be that..I doubt I'll find any research about it, but I'll have a look...could be interesting.

People don't realise what awful stuff iodine can be. When I had a slipped disc op, they asked me if I was allergic to iodine, and I said I didn't know. Turns out I was, and I was in absolute agony for 36 hours after the op, the iodine burning my back, before they found me a morphine pump - which, incidentally, they'd promised me straight after the op, but which didn't materialise. And the nurses refused to believe I was in such pain. Very bad memory.

Anyway, it is well-known that excess iodine can trigger Hashi's.

I'm sorry for that, shouldn't have happened! I wonder why they didn't give you the pump? Wonder if it wasn't suitable at that stage..either way, you don't leave your patient in pain! Causes all sorts of well as being ethically wrong!

My fiance, had a microdiscetomy at the age of 21; since then he sometimes collapses and has IBS type symptoms...I'm all for surgery, but so many people don't take it seriously and surgeons sometimes push a bit too much..

Are you allergic to shellfish?

The things is there's pros and cons to different skin preps...maybe more work needs doing into the long term issues associated with various skin preps.

I'm always (well I've been off work for months..) getting iodine on me.

I can only find studies looking at topical iodine exposure and hypothyroidism in infants. I guess they don't wanna put people off working in health care..maybe I need a career change, somewhere which isn't bad for my health. I've had blood in my eye, had a doctor fall on me aha....the list goes on.

Well, you were hardly responsible, I had the op in France! lol They said there was a 'mix-up' in post-op. Well, that was one version. Someone else said there weren't enough morphine pumps to go round - and I drew the short straw! The anesthésiste said that I was never promised a pump in the first place! Lying sod.

No, I'm not allergic to anything - except iodine! It was just an awful hospital, and I would never go there again! Last time I had to be hospitalised, I staged a sit-in in my kitchen until the ambulance men promised to take me to another hospital, a bit further away. Caused an awful lot of upset all round, but I stuck to my guns. I left that other hospital thinking well, the staff were nicer, but it was just as much of a shambles as the other one! The right hand had no idea what the left hand was doing, and confusion reigned. My notes are a complete work of fiction!

Sounds like it is dangerous being a theatre nurse. Probably being a nurse anywhere in a hospital. So many things could go wrong, so many potentials for an accident. You must be very brave!

I know, but working in health care..makes you feel a bit sad knowing someone didn't receive decent care. I'm an operating department practitioner, bit different to a's a weird job to nan always calls me a nurse, I give up aha. I'm not brave, I just wanted to work in the NHS; my mother had a kidney transplant before I was born, she's had an awful lot of issues, I had necrotisingentercolitis and other health issues, so I wanted to 'give back' the care my family had at the time my uni course was free... unfortunately, just like nursing and midwifery...thats no longer the case. A big shame.

Yes, it's a terrible shame. 'Progress' doesn't always mean going forward. Sometimes, it's going back. :'(

Definitely. I feel that it puts people who would be suitable, off applying to university. Just because you can afford university doesn't mean you should be there..ive seen it on multiple occasions. I'm just talking to an old colleague of mine..from when I worked in a different trust, she had to give up her career due to her thyroid. Many theatre staff seem to have autoimmune issues. I mainly work in anaesthetics, so I breathe in an awful lot of different gases and vapours..I don't know if there's a link there, but I'm gonna keep looking. I don't want to change my career, but if evidence suggests I probably should..then maybe I will...

I sincerely hope you don't have to.

Me too. Thanks for your help today. I appreciate it.

You're very welcome. :)


So has your GP increase dose to 50mcg?

You are seriously under medicated to have TSH so high

Your FT4 is most likely high as you took Levothyroxine before the test

A thyroid specialist will always tell patient NOT to take Levothyroxine in the 24 hours prior to test

So if you normally take Levo in morning, delay until after test, make sure to get test as early as possible in morning and fasting too. Take your Levothyroxine immediately after test. Wait at least an hour before breakfast

What about vitamin D? Have you had this tested?

Low vitamin D is extremely common with Hashimoto's

Low magnesium often present if you have low vitamin D. Good level of magnesium is essential for heart health

What beta blocker are you on? Heart is likely struggling due to being in such low dose

Hey, I'm not on bisoprolol because on the day of going to my GP my heart was messing around; he caught it at 120, but it had slowed down at that point. No, aha they have kept me on 37.5mcg levo at the mo..gonna retest soon and not take levo till endocrinology consultant, well I no longer deal with him after what he said..

Vitamin D is over 100; I took high dose for 8 weeks and maintain it. Magnesium was lovely too, I can't remember how much right now, but it was near the far end of the range. Thanks

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