Hi please can someone tell me how long it takes for an increase of 25mcg of levothyroxine to work.
I have been on 100mcg levothyroxine for many years, but I have recently piled on about 1 stone in weight & noticed issues with memory/forgetfulness, brain fog, apathy, & very bad depression. Because of this, I looked up arecent blood test result & found my thyroid (TSH is it?) had gone from 2.70 last June to 3.89 this march.
My doctor has increased levothyroxine by 25mcg, & I have been on it about 2 weeks & even though the TSH is now down to 2.09, I still feel very strange. Is this blood test reading relevant to how you should feel, or is it there a kind delay to actually feeling any benefit?
I have always had these symptoms to a lesser degree with years of stress, anxiety & depression, and medicated with antidepressant & so on, & I am not sure if it connected, but I noticed these symptoms started about 6-8 weeks after halving the dosage of an antipsychotic.
Thank you.
Ian
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Ian232
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Ian232 it is likely that you will need an increase of at least 50mcg to get your TSH under 2. Most members report feeling best with TSH significantly below 1. For a complete picture of your thyroid health, ask for FT4 and FT3 to be tested alongside TSH.
Most GPS and even some endocrinologists don’t routinely test FT3 and some only test FT4 if TSH is not in range. That’s why so many forum members test privately for TSH, FT3, FT4, thyroid antibodies and key vitamins (ferritin, folate, vitamins D and B12). Many members use Medichecks or Blue Horizon
Increased anxiety has been the worst symptom of having a thyroid condition for me and it is always worse if thyroid medication or key vitamins (ferritin, folate, vitamins B12 and D) are not optimal. Remember that ‘optimal’ is not the same as ‘normal’ or ‘within range’. Do post any blood test results in a new post when you get them, so members can offer better advice.
We are here to help and support, so keep posting! 🦋
Thank you for your replies! This is all new to me, but yes I dont think I have ever had a proper thyroid test done, so I will look into getting further tests done. I think the B12 test looks fine & constant from previous tests.
you need to give it longer .. unlikely to feel anything much until about day 7-10 at the earliest and 2 weeks is to soon to retest TSH .. it can take TSH about 6 weeks to move/ settle down again in response to new dose .. and similarly symptoms can keep changing / improving over that timescale too.
TSH has a bit of delayed reaction to changes in thyroid hormone levels (T4 and T3 are the thyroid hormones .
TSH (Thyroid Stimulating Hormone) is just a feedback message from the pituitary to the thyroid (asking it to make more /or less T4/T3 in response to the T4/T3 levels in the blood) ... it's a kind of 'window into the T4/T3 levels of the last few weeks' , rather than a picture of what they are today.
See what your result show after 6 weeks on 125mcg .. lot's of people feel best when TSH is 1 or under.. (but not everyone) .
If you still have hypo symptoms after 6 weeks and TSH is still over 1 / fT4 is not too high in range , then ask GP to increase dose a bit more .
all of then recommend GP's keep TSH (Thyroid Stimulating Hormone) between 0.4 /0.5 and 2.0 / 2.5 in all patients on levo .. (so having TSH at the bottom of the range is deemed ok if you feel better with it there)
To be honest, I basically get what I am given at Tesco pharmacy, & having differing brands has never crossed my mind before, so I am not sure, but I think it does occasionally change.
I have generally been taking my levothyroxine each morning at 8.00am with water, followed by an antidepressant (75mg venlafaxine) about 35-45 minutes later, which I now understand is not ideal.
Many people find Levothyroxine brands are not interchangeable.
Most easily available (and often most easily tolerated) are Mercury Pharma or Accord
Mercury Pharma make 25mcg, 50mcg and 100mcg tablets
Mercury Pharma also boxed as Eltroxin. Both often listed by company name on pharmacy database - Advanz
Accord only make 50mcg and 100mcg tablets
Accord is also boxed as Almus via Boots,
Many patients do NOT get on well with Teva brand of Levothyroxine. Teva is lactose free.
But Teva contains mannitol as a filler instead of lactose, which seems to be possible cause of problems. Mannitol seems to upset many people, it changes gut biome
But for some people (usually if lactose intolerant, Teva is by far the best option)
Aristo (currently 100mcg only) is lactose free and mannitol free.
If a patient reports persistent symptoms when switching between different levothyroxine tablet formulations, consider consistently prescribing a specific product known to be well tolerated by the patient.
Physicians should: 1) alert patients that preparations may be switched at the pharmacy; 2) encourage patients to ask to remain on the same preparation at every pharmacy refill; and 3) make sure patients understand the need to have their TSH retested and the potential for dosing readjusted every time their LT4 preparation is switched (18).
Levothyroxine is an extremely fussy hormone and should always be taken on an empty stomach and then nothing apart from water for at least an hour after
Many people take Levothyroxine soon after waking, but it may be more convenient and perhaps more effective taken at bedtime
No other medication or supplements at same as Levothyroxine, leave at least 2 hour gap.
Some like iron, calcium, magnesium, HRT, omeprazole or vitamin D should be four hours away
(Time gap doesn't apply to Vitamin D mouth spray)
If you normally take levothyroxine at bedtime/in night ...adjust timings as follows prior to blood test
If testing Monday morning, delay Saturday evening dose levothyroxine until Sunday morning. Delay Sunday evening dose levothyroxine until after blood test on Monday morning. Take Monday evening dose levothyroxine as per normal
Similarly if normally splitting your levothyroxine, take whole daily dose 24 hours before test
Increasing number of members find it smoother/more tolerable to split levothyroxine as two smaller doses, roughly half dose waking, half dose at bedtime.
As a chap request GP test testosterone levels 3-4 months after increasing levothyroxine dose
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