what blood tests should i ask for?: hi i was... - Thyroid UK

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what blood tests should i ask for?


hi i was diagnosed with hypo 2 months ago ive been on 25mcg levo since. im getting bloods done next week to see how my levels are they nornally just check t4 and tsh. should i ask them to do t3 or is there no need? also i would like to have my b12 checked what else should i ask for, can u ask to have all vitamins checked? ive been suffering with vertigo/dizziness


danielle x

17 Replies

To be honest, 25mcg is a ludicrously low dose, and all it is likely to do is make things worse rather than better.

I would say definitely ask for the T3 to be checked but often even if the GP asks, the lab will not do it. Hopefully yours will be the exception that proves the rule. Also B12, D, folate, ferritin would be useful because even when optimally dosed, low levels of these can make you unwell and even unable to utilise the Thyroxine.

Until you are on a sensible dosage of Thyroxine it will not be effective. That dose is even lower than the dose suggested as a starting dose for frail elderly patients or those with heart problems, certainly not the normal starting dose. Your GP must either be terrified of Thyroxine or he/she is dubious of the diagnosis.

Do please put any results you get on here including the ranges to enable you to get better support and advice.

danid1989 in reply to marram

my levels were just a little low thats why he said hel just try me on a small dose first as my tsh was rising a little. it hasnt gave me the typical feeling tired putting on weight and feeling cold. i have none of those symptoms just dizziness and we dont know if thats even the thyroid causing it as my bloods wer normal when the dizziness started. so who knows. il find out more when i get bloods done

PinkNinja in reply to danid1989

That makes sense if you're only slightly hypothyroid. Slowly but surely is best. If your levels had been very low you would have needed to start on a higher dose. You may find that you do need increases as the months and years go on if you have caught this early. Just keep an eye on your symptoms and blood results, although blood results are of limited use on their own.

My vertigo seems to be related to B12 so that is definitely worth getting checked. The NHS reference ranges are pretty rubbish though. I think they must have been designed to determine whether injections are required or not as the level is extremely low. Many doctors who know about this area recommend a level above 500 to prevent neurological damage. Unless your level is below the healthy range you will need to supplement yourself as the NHS won't. If you manage to get this tested, let us know your results and we will be able to point you in the right direction for research articles and recommendations about B12.

Caorlyn x

danid1989 in reply to PinkNinja

you get vertigo too? i feel like im on a boat ive had this since january x

PinkNinja in reply to danid1989

Yes. Taking 5000mcg methylcobalamin (vitamin B12) for a couple of months and 1000mcg since then means I haven't had vertigo hardly at all. I ran out a couple of months ago and the vertigo came back. Within a couple of days of starting the B12 again, the vertigo went. I still get it a little bit when I move round quickly but most of the time I don't have a problem with it any more :)

It can be caused by a B12 deficiency but it can also be caused by other things such as infection or underactive thyroid.

I hope you find the solution. Vertigo is horrible and so debilitating :(

Carolyn x


Hi Danielle

I was put on 25mcg of levo at diagnosis and I'm neither frail or elderly! It took my body many months to adjust back to having T4 in my body and I think some of my issues were related to this. Things did settle well for me after 6 months and I did well on 25mcg for several months.

After a year, I had a return of symptoms and needed an increase up to 50mcg. We are all different and I'm very sensitive to levo - a small amount can make a big difference to me. I'm now really well again.

I track my symptoms using Thyroid UKs list and keep a record of everything. I discuss all of my concerns with my GP - I write everything down before I go in - and try to work with them as they have a full picture. I don't let them get away with 'your results are normal, go away' if I have any concerns about my symptoms, treatment and management of the condition.

Good luck!


PinkNinja in reply to Hidden

I'm pleased to hear you have a GP that listens to you. That is half the battle with this awful disease! :)

Hidden in reply to PinkNinja

They needed some re-training, I can assure you - good job I'm a stroppy, stubborn old bird ;) And it is indeed half the battle - that and working out which guidelines truely are NICE and which ones are just medical politics and not very nice at all. :)


In my opinion, you should definitely be given an increase in medication up to 50mcg with another increase in about six weeks when you should have another blood test.

Always get copies now of your blood test results for your own reference and if you have a query you can post them on a new question complete with the ranges (which are important).

Some GP's insist in keeping you within the 'reference range' but it doesn't always suit some patients and they have continuing ill-health.

It's back to the old rule which applies to everyone.

If you feel fine, don't mess about. If you DON'T feel fine, then quite clearly you need something different. I would say that vertigo/Dizziness definitely comes into the category of not feeling fine. I was constantly suffering from vertigo and dizziness because my low thyroid levels were affecting my immune system and I had constant ear, nose and throat infections, often with no other symptoms.

The doctor clearly anticipated that after about 8 weeks you would need to be re-assessed. A rising TSH is a matter for concern and it's great that your GP was on the ball enough to see how things continue.

danid1989 in reply to marram

i had no idea thyroid would cause dizziness and vertigo i have had it since january feel like im on a boat. is a rising tsh bad? i think it was 1. something and my t4 was 10.4

marram in reply to danid1989

The TSH will vary naturally depending on the time of day that the blood was taken, it will be lower in the morning and higher in the afternoon, so if the variation is due to different blood test times, then it would not be anything to worry about. If, on the other hand, it were an upward trend every time the blood is taken, it could be an indication of reducing thyroid function.

For many people, a TSH of 1 point something would be perfectly normal, or even higher. But for me, that level would be too high. I had a TSH of 1.4 in December and I was unable to function on any level, my heart was enlarged and I was getting palpitations, and my cholesterol was 9.7. I had breathing problems, balance problems, constant pain and almost permanent exhaustion, insomnia, hair loss and skin rashes. I was unable to fight infections and had an almost constant cough.

Almost nine months on, my TSH is 0.03 and I am a different person. I am pain free, my cholesterol had fallen to below 7 in June (my next test is due shortly), I have not used either of my inhalers for over six months, I am sleeping better most of the time, I have lost a stone in weight, I am more active, I can get through the day without falling asleep as soon as I sit down, even my face has changed shape. I now recognise myself in the mirror!

What this shows is that the actual 'normal' TSH can vary from person to person, there are some on this forum who are well with a TSH over 2, and then some like me who are only well with a TSH of well below 1.

It seems a good idea to get B12 and folate and ferritin plus vitamin D checked, it all can contribute to feeling unwell. If all these are fine and you are still unwell, then the doc needs to look further. I do hope that you can get to the bottom of this vertigo problem, it's horrible. Have you had your ears looked at, just to see they are OK?

You do not say if you have any other signs or symptoms which could indicate low thyroid, what led your GP to test thyroid levels in the first place?

Marie XX

danid1989 in reply to marram

he checked them because of my dizziness i think its pretty routine here for them to check it. ive seen an ent he said he doesnt think its an inner ear thing.

funny thing is ive symptoms of overactive ive bad anxiety, racing thoughts, palpitations, weight loss and a few others.

it all started with a vomiting bug i havent been the same since. got bloods taken in jan wen this started and my thyroid normal it wasnt until a few months later the thyroid went low.

mystery xx


Hi Danielle,

Unfortunately, all doctors seem to have their own way of dealing with thyroid disease. Some will start at 25mcg either because they are frail or elderly or just because they want to see what happens. Generally, patients are started on 50mcg first and then it is increased if the thyroid tests deem it so.

However, from experience, I know that everyone is very different and 25mcg for one person will send them over causing palpitations whilst another person will feel nothing on 50mcg.

Because of this, it's often a case of trial and error, unless, of course, the patient is massively underactive and then it's important to get as much thyroxine into their system as possible as soon as possible.

I would say, it's always a good idea to keep a journal so that you can see where you feel best i.e. test result level, dosage level and the level at which your symptoms improve. Lyn

My dizziness/vertigo were definitely thyroid related. I used to feel that I was on a boat too - it was very unpleasant :(

Thankfully I am feeling fine now that I am on sufficient thyroid hormone replacement (in my case NDT).

Hope you feel better soon. xx

danid1989 in reply to Clarebear

how long did your dizziness last? x

Clarebear in reply to danid1989

I started with the dizziness/vertigo before diagnosis at Easter 2011. I was diagnosed and started thyroxine in the July but did not do well on it (most people do though at the right dose).

The following jan I started on NDT and it was probably another 6 months before I started to feel better, as I found increasing the dose really hard. A year on from that and I haven't had any problems since then with the dizziness/vertigo.

Hope yours improves soon. Clare x

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