I’ve been on 100mcg levo for approx a year but over the past three months have felt debilitating brain fog, affecting work performance. It may not relate to my thyroid at all but I wondered if anyone had experienced brain fog when under/over medicated? I know I’m on a dose that’s probably too low for my current weight (I’m overweight by about 4 stones) but read that it relates to your ideal weight and not actual.
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Hoop1888
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Brain-fog is usually due to under-medication. Dosing by weight is a ridiculous notion and shouldn't be taken too seriously. Not all the people who weigh the same have the same needs, or the same capacity to absorb, either in the gut or at the cellular level.
but read that it relates to your ideal weight and not actual.
And that would make it even more ridiculous! I cannot put it into words but that idea is just so stupid...
The way to know if you're under-medicated is - first and formost - how you feel. And secondly, back it up with blood tests. Not by how much you weigh. Do you have a copy of your latest blood test results? If so, post them here - with the ranges - and let's have a look.
If not ….request a blood test including thyroid antibodies and vitamin levels
Bloods should be retested 6-8 weeks after each dose change or brand change in levothyroxine
For full Thyroid evaluation you need TSH, FT4 and FT3 tested
Also both TPO and TG thyroid antibodies tested at least once to see if your hypothyroidism is autoimmune
Very important to test vitamin D, folate, ferritin and B12 at least once year minimum
Low vitamin levels are extremely common when hypothyroid, especially with autoimmune thyroid disease and when under medicated
About 90% of primary hypothyroidism is autoimmune thyroid disease, usually diagnosed by high TPO and/or high TG thyroid antibodies
Autoimmune thyroid disease with goitre is Hashimoto’s
Autoimmune thyroid disease without goitre is Ord’s thyroiditis.
Both are autoimmune and generally called Hashimoto’s.
Significant minority of Hashimoto’s patients only have high TG antibodies (thyroglobulin)
20% of autoimmune thyroid patients never have high thyroid antibodies and ultrasound scan of thyroid can get diagnosis
In U.K. medics hardly ever refer to autoimmune thyroid disease as Hashimoto’s (or Ord’s thyroiditis)
Recommended that all thyroid blood tests early morning, ideally just before 9am, only drink water between waking and test and last dose levothyroxine 24 hours before test
This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip)
Private tests are available as NHS currently rarely tests Ft3 or all relevant vitamins
if I was dosed by weight I’d be over medicated for sure. You should really go by blood tests and what your levels are alongside your symptoms. I’ve only had brain fog when I’ve been under medicated in the past. I feel lucky that I’ve managed to get symptom free by checking my levels every 3 months and getting the right daily doses for myself. I spilt my doses daily. I feel this helps too. I keep my levels in range and TSH around 1.00.
Yes defo next step is private thyroid test.You may need more levo or maybe your conversion of T4-T3 is poor,the function test is only way to tell for sure.Brain fog,weight gain,constipation and joint pain are my main symptoms when under medicated and these seem very common amongst others.
I suffered brain fog and memory/ concentration issues for years and put it down to thyroid issues. I started testosterone a few years ago and the brain fog went completely. For me memory/ concentration and brain fog are two separate things as I still have them issues which are causing massive issues daily.
Brain fog might not be what others have but to me it was like a disconnection with my eyes and brain and feeling very spacey like I wasn't present. This really affected my driving and only drove when had too. I couldn't speak or listen to music in the car as my visual perception was terrible.
Once on testosterone this all cleared up amongst alot of other issues which too I blamed an thyroid.
I've been on hrt about 8 years and only when added testosterone did things feel normal again
Would you be willing to share what your testosterone levels were before and after TRT treatment? Im having brain fog issues on thyroid meds + low testosterone and am trying to piece the puzzle together
Hi, yes my testosterone level was 0.5 then went to 1.5. I was prescribed T mainly on my symptoms but blood testvis done to to check your level isn't already top of range, doesn't have to be really low to get prescribed.I have found my brain fog has come back recently as I'm struggling to drive again feeling the disconnection again. My last test level had dropped so I know i need to increase but waiting on bloods I had done today before I do.
Wait times for meno specialist is now ridiculously long, over 18 months some ladies wait.. just criminal.
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