I was wondering when the best time is to take levothyroxine - before or after a blood test.
I had a test done a few weeks ago, the GP said my thyroid was impaired. The next test I took the medicine 2 hours before the test. This time they said I was overmedicated and reduced my dose by 25 mcg.
Since then I've had symptoms of hypothyroidism and my concentration is so bad it's difficult to work.
Is it worth my time going back to the gp, it's only been 7 days since the reduction, or should I persevere hoping things settle down? Is it possible taking my meds before the test gave a false reading?
Recently I've been losing a lot of weight, been nervous, and have a pronounced tremor, especially in the afternoon. After more blood tests the Levothyroxine was reduced to 125mcg again, even though I expected the dose to be increased.That was a week ago.
Since then I've been feeling the cold, cold hands and arms, fatigued, cloudy headed, feeling generally unwell most of the time. In the afternoons, I start to feel the heat, the nervousness comes back, along with the tremor. In the evenings the coldness and the brain fog and the fatigue.
Weight loss, tremor are possible symptoms of too much levothyroxine …..so you would expect dose reduction
Reducing dose inevitably results in some hypo type symptoms initially
What where Ft4 and Ft3 results in most recent tests
ALWAYS test thyroid levels early morning and last dose levothyroxine 24 hours before test
ESSENTIAL to test vitamin D, folate, ferritin and B12 at least once year
When were vitamin levels last tested
What vitamin supplements are you currently taking
Do you have autoimmune thyroid disease, also called Hashimoto’s, usually diagnosed by high thyroid antibodies
Thanks for your post, you answered one of my questions after I edited the post, that the test should be done 24 hours after my last dose.
I was actually expecting an increase in levothyroxine, my heart resting heart rate is 60bpm and I'm cold and fatigued a lot of the time. I think I'll ask for the test to be repeated. I've experienced overactive thyroid before, and I don't think that was it.
I've had vitamins etc checked recently. My gp only gives me vague indications of what's wrong with my blood tests... I've still not seen them face to face.
You are legally entitled to printed copies of ALL your blood test results and ranges.
The best way to get access to current and historic blood test results is to register for online access to your medical record and blood test results
UK GP practices are supposed to offer everyone online access for blood test results. Ring and ask if this is available and apply to do so if possible, if it is you may need "enhanced access" to see blood results.
Hi ask for a print out of your blood tests at the reception l always do obviously you have to wait till tests are in so go there about 5 working days after your blood testBest Wishes
I don't know a lot about hypothyroidism caused by lithium... what my previous consultant told me is that lithium has entered my kidneys and damaged the thyroid cells ( I think that's what she said). At time of diagnosis TSH was at 95% - my consultant hadn't seen anything like it. My thyroid just couldn't produce hormone any more. Which is why I can appreciate why I may need more levothyroxine over time, but I can't see why I would ever need less - according to my consultant my thyroid will never recover. My thyroid meds are now managed by a GP, not a doctor who specialises in prescribing lithium. Which is why I think I need advice... apparently in cases like mine there are certain considerations to take account of when reading the blood tests, but I can't remember what they were.
I remember an episode of Homeland where Carrie was told her Thyroid was damaged after she had been held as a prisoner for many months but that was because she hadn't had access to her lithium while being held captive. This is the only reference I have heard in relation to lithium and thyroid which would be rather extreme if not a TV show!
I had the dose reduction 8 days ago...
I've been feeling steadily worse to the point it was getting difficult to concentrate to work today, and I gave up trying to study after 20 mins. I suppose I just don't want it to stay the same or get worse.
Sane brand of levothyroxine every time.
I registered for online records when I stayed in England last year, they gave me login details, but I couldn't access anything. We moved back to Scotland last year - I've not tried to access online services, the practice website states I have to apply to the practice manager for access to my records. I'll contact the practice tomorrow or Thursday.
If your medication is levothyroxine then it shouldn't make much difference but if you take anything with T3 in it you should ALWAYS take it After your blood test. It wouldn't hurt to do that with levo either. Do you know what your blood test results were? Inability to concentrate can be a symptom of either over or under treatment unfortunately.
My concentration problems occurred after the dose reduction 9 days ago... at the moment I feel cold, mildly depressed, achy, and slowed down and tired. I'm mostly concerned because this may affect my ability to work.
I'm going to request my blood results, as the last letter from the GP said "last increase was too small, test again after 4 weeks, if still imbalanced adjust then." Vague I know, I assumed they meant my last increase in levothyroxine a few months ago wasn't enough, and my thyroid was undermedicated.
in reply to
I phoned and spoke to the nurse. My last two tests were 0.05 and then 0.1 tsh, which is why Levothyroxine was reduced.I told the nurse my concerns and she said to wait 2 or 3 weeks and come back to them if I still felt unwell.
I took a home test today, I don't know how reliable they are, but it was positive for hypothyroidism. If accurate could my tsh have changed so much in just over a week?
The nurse told me my t4 had been within range at the blood tests. I was at work today so I've not been able to obtain more detailed results
it's hard to be sure how accurate those at home TSH positive/ negative tests are not many people have used them on here ... if it said positive then it thinks TSH is over range ie. over 5 ish~ which does seem highly unlikely to be correct just 7 days after TSH was 0.1 and when dose was only reduced by 25mcg .. but , regardless of whether the test itself is reliable , testing a week after a dose change is not going to give a true picture of what TSH will be once the lowered dose has had time to settle in ..so i think you have to ignore that home tests result for now.
you do sound like you had symptoms of overmedication before they reduced dose weigh loss/ tremor etc ,,
if you'd felt fine before the reduction i'd say argue to have the dose put back up because fT4 is in range ... but you weren't feeling ok, you had symptoms that fit with too much levo , and the tsh was very low twice , so i think you're probably best to stick it out on this dose for few weeks now you've started and wait to see how it feel when it's settled in.
hopefully things will improve a bit over the next couple of weeks rather than get worse .
if not then perhaps dose needs to be increased a tad to 112.5 mcg .
Sorry that not a nice prospect when you're worried managing at work , but it is really too soon to test again just yet
. i felt really awful (and constipated) the first couple of weeks when my dose was reduced .. then it was a bit more ok .. and gradually improved again. i'm glad i stuck it out for a few more weeks as it was better then the previous dose in the end .
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p.s if in future you are asked to reduce dose just due to TSH being low , but you actually feel perfectly ok ,and are worried a dose reduction will leave you feeling 'not ok' .. then this may come in useful: healthunlocked.com/thyroidu... useful-evidence-that-tsh-between-0.04-0.4-has-no-increased-risk-to-patients-on-levothyroxine-updated-new-study-does-show-small-risk
Thanks for your reply, all the information is very helpful.
I maybe muddied the water - the tremor may be caused by lithium or another 2 medicines I take, I'd just noticed it was more pronounced along with nervousness which I often have.
I had overactive thyroid 20 years ago and it resolved itself without medical intervention after 10 months. Recently wasn't anything like that, I've never felt overheated or fast heart etc, quite the opposite.
The weight loss wasn't recent either.
I honestly think there's been a mistake. I'd been taking 150mcg of levothyroxine for months without problem, I can't imagine there would suddenly be such a big change in tsh all of a sudden. I think they reduced the dose by too much.
yes very tricky to know what's causing what then .. mind you, symptoms of being 'a little bit overmedicated' won't necessarily feel the same as how being properly hyper felt .
and we can somtimes need less than we used to ...I became a bit overmedicated a few yrs ago after being stable on 150mcg for 15 yrs , and had nasty kidney pain/ urine ,bladder symptoms , fine tremor, weight loss , anxiety / catastrophising about everything , and was physically really jumpy .. but my heart hadn't speeded up noticeably and i wasn't too hot at all ... but all improve after few weeks on lower dose .
What level is your TSH normally at when you've felt ok .. do you know ?
Time of last dose levo does have a noticeable effect of fT4 result Redditch ... not as big an effect as T3 dose ,true, but it's still a noticeable effect .
See the 2nd reply to this post for graph: healthunlocked.com/thyroidu... suggested-thyroid-hormone-test-timing-protocols
the connection between thyroid disorders and lithium is well documented.
i think you need to find the letter from the consultant who details your health issue and give a copy of this letter to your new doctor in Scotland.
I would also ask to be referred to an endocrinologist who is able to understand the consequences of this drug and dose your hypothyroidism accordingly as you clearly feel this new doctor is not helping you.
Do you have any current Free T3 and Free t4 readings and ranges to share with forum members ?
No thyroid hormone replacement works well until your core strength vitamins and minerals are up and maintained at optimal - do you have any readings of ferritin, folate, B12 and vitamin D ?
Robd4 taking levo 2 hrs before test will have given a higher fT4 result than if you had left a longer gap ... but it doesn't affect the TSH result .
There is a peak in fT4 levels lasting from about 2 hrs after dose until about 6 hrs after dose then it falls gradually until about 12hrs after dose , by which time it is more or less at it's settled level.. but since these timing will vary quite a lot depending on the individuals speed of digestion / absorption , then for consistent testing it's best to leave a 24hr gap and always test at same time of day .
The TSH result is affected by the time of day.... it's highest in the early morning gradually falling to its lowest in mid afternoon , then gradually rising again. so best t test at 8/ 9 am consistently . .. (see link in my reply above to Redditch)
TSH at 9 am can be lowered by up to 30% by having breakfast before the test (this affects some people more than others, no way of knowing if it affects you or not ) ...so for the most consistent / comparable results it's best to have early am test. (with no breakfast ) , 24 hrs after last dose , and then have levo straight afterwards.
If your GP reduced the dose based on just a TSH test , then the 2 hr gap will not have affected their decision to lower your dose , because TSH is not affected by time of last dose ..
BUT if they also tested fT4 and IF fT4 result was high / over range . then yes, the 2 hr gap may have made a difference top their decision .. ie. if you'd tested correctly @24hrs and fT4 was lower/in range , they may not have reduced your dose .
as for how you feel now ... when reducing dose it is usual ( for me anyway) to feel a bit undermedicated for a few weeks before your body adjusts itself to the lower dose , for me the first couple of weeks i'd expect to be a bit constipated / brain dead/ , then another couple of weeks of feeling a bit flat / not with it ...by week 5 when thing have started to settle and i can start to get a reasonable idea of whether the new dose is actually going to be ok or not. If it is going to be ok, things will be slowly improving from week 5 onwards .. so basically i'v learned to ignore how i feel for the first 5 weeks after a dose change and wait it out .
i now realise that in the past i've been far too quick to make my mind up about how a new dose will feel . if i'd been asked at 7 days or 2/3/4 weeks i'd have been absolutely adamant that the new dose was too low and put it back up.. but by 2/3 months it was apparent that it was an improvement on how i felt on the previous dose.
25mcgs / day is actually a fairly big reduction.. 12.5mcg is often enough to have an impact on how you feel and on blood results , so it may have been better to lower by a smaller amount eg 12.5mcg /day .... but it;s difficult to be more specific about what is going on until you get hold of the blood results that led to this reduction.
Sorry for then length .. my brain has lost the ability to be concise this morning ....
Thanks for your reply. Having bipolar as well I think I tend to pay more attention to symptoms... blood tests are something I don't know much about. I tend to react to symptoms quickly to avoid illness developing.Maybe I need to recognise I have 2 different illnesses managed 2 different ways.
you might be right ... proper thyroid management is a bit like managing a Tortoise.. you have to wait quite a long time to see what direction it's going in.
never had the pleasure of bipolar, but i imagine it's more like managing a Hare ... or perhaps a Frog.
The management for bipolar is larger doses of meds for acute episodes, then smaller doses of the same meds for maintenance treatment. I've been episode free for 11 years thanks to the meds and managing my stress.
Management is often making lifestyle changes to respond to and manage stress, rather than making medicine changes, unless they're needed.
There isn't a blood test for psychiatric conditions, so they rely on observation - signs and symptoms.
Hence my approach with my thyroid condition... I'm used to taking management of illness into my own hands... it's rarely I need to be treated with medicine changes. It's great that the thyroid illness can be managed by blood tests and medicine changes, I now think I've had the condition for 14 years and I've been poorly educated or involved in it's management. I guess it's not too late to learn.
yes .. learn as much as you can , because many GP's will try to adjust your levo dose based JUST on your TSH result, without looking properly at your symptoms or your fT4 / fT3 results ..which can have serious consequences on your life it they get it wrong .
I spoke to the practice nurse. She told me my t4 levels had been in normal range both blood tests, but tsh had been 0.05 4 weeks ago and 0.1 two weeks ago. So they decreased my levothyroxine dose. I've not requested full results yet.
You’ve definitely received some great on point advice here. As a 30 year Thyroid patient I would also suggest that you ride it out for 5 or 6 weeks after a dosage change.
(Keeping in mind though that symptoms for being over medicated can show up as early as a week after dosage change. And should surely be paid attention to.)
I have received some great advice... I understand now I'll need to be patient and see what happens. I think I was panicking because my work contract has been extended with the understanding I won't be having too many sick days - if that wasn't the case I wouldn't have gone into work yesterday. I'm one for fixing unnecessary problems, and blood results aside the change in dose seems to have had a disproportionate effect on my physical health and we'll being compared to the mild hyperthyroidism symptoms I may have been experiencing.
I guess I've lost trust in the GP's management of this condition... I have a half day so I'll try to request my blood test result tomorrow.
Thanks to everyone for their help, I appreciate it. I'm just feeling frustrated with this experience, but I know the next steps I need to take - get my blood test results and patience.
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