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Thyroid UK
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tsh 100, free t4 <5

hi, been recently diagnosed with hypo by chance after a kidney doctor was trying to find out why I had high creatinine and reduced egfr in my kidneys, my gp said worst results he had come across himself? told me I'm on levothyroxine for life but the good news was free prescription, this was after telling me I had dehydration/virus for 3 months causing the brain fog, bad concentration, acheing etc. I went through a period of feeling pretty lousy but gradually felt a lot better even before I was put on levo, tbh I thought I was suffering from anxiety and when I feel stressed or think to much about the hypo and ckd I do feel worse so I try and stay busy and surround myself people which takes my mind of it and really helps. I have read quite a bit on here about tsh levels but cant find a lot about free t4 under 5, my doc said that's the important bit?, are there any questions I should be asking my gp about this, he seemed more concerned if I start feeling depressed to go back to the surgery, I have only been on 50g of levo for 1 week and I know from reading not to expect to much to soon, just wondering with my results so far out why I'm not feeling as lousy as some of the people on here?

5 Replies

Welcome to the forum, Finny70.

It's a funny thing but the highest TSH is often found incidentally during other tests whereas patients with borderline TSH often feel desperately ill but can't get a diagnosis until TSH is over range. The good news is that when people are diagnosed with very high TSH they often make a faster and better recovery than others. Kidney function will become compromised with low thyroid hormone and should improve when optimally medicated with replacement.

TSH is a pituitary hormone which rises in response to low thyroid hormones T4 and T3, and drops when sufficient hormone is detected. T4 is a storage hormone which converts to T3. T3 is the active hormone which makes us feel hypothyroid when it is low. T4 ranges vary and if your range is typical 12-22 you'll see how far below range FT4 5 is. Low FT4 means FT3 will be very low indeed. 'Ideal' FT4 will be in the upper quadrant >18 and most people are comfortable when TSH is just above or below 1.0.

It takes 7-10 days for Levothyoxine to be absorbed so it may not be working yet, and it will take up to 6 weeks to metabolise the dose before you're likely to feel any improvement in symptoms. Don't push yourself hard, hypothyroidism can be very debilitating until thyroid levels improve and you should rest as much as you can, including day time naps if you need to.

50mcg is a conservative dose and will need increasing every few weeks until your thyroid levels are optimal. Dose increases are usually in 25mcg increments every 6-8 weeks but your GP may choose to increase at a higher dose and every 4 weeks while your TSH remains high.

Members are advised to have early morning, fasting (water only), tests as TSH is highest early and drops postprandially but you don't need to bother until your TSH is <5.0. You must always take Levothyroxine after your blood draw though as it will skew results.

Vitamins and minerals can be trashed as we become hypothyroid so ask your GP to include ferritin, vitamin D, B12 and folate on your next blood request form. You might also ask him to test thyroid peroxidase antibodies to confirm or rule out autoimmune thyroid disease (Hashimoto's) as a cause of your hypothyroidism.

Get into the habit of asking for a printout of blood results and ranges after every blood test. It's helpful to track your progress and to post them when you ask question on the forum.




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Hi Finny70, I was diagnosed 18 months ago with a TSH of 240 - also the highest any of my doctors had seen. Like Clutter says, although it took about a year to feel really good, I have made an excellent recovery on levothyroxine (gradually increased 25 to 125mcg), and apart from taking my tabs in the morning I forget I have got such a serious disease. Take it easy and allow your body to adjust - I started to really feel better after 4-6 weeks and have mostly gradually improved since then. Good luck :)

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Just a thought - do you have high cholesterol? Being hypothyroid raises cholesterol, so now you are on Levothyroxine you should find your cholesterol improves and you no longer need to take statins (if you are).


thanks for the quick replys, my kidney doctor is holding off any further action other than monthly blood tests to monitor my kidney egfr % working rate which is around 44-49%, I did speak to him about hyporthyroid making my creatinine high and egfr low, he said he hadn't heard of this but actually seemed quite interested in seeing what happens once the levo gets in my system, it was another kidney doctor that mentioned having thyroid blood test. the nurse at my gps did the test with my last set of bloods for kidney doctor, I'm glad I asked about it now. I will ask my gp about extra tests next time I see him although when I mentioned the vitamins checks to the kidney doctor he said all my other bloods were ok. my cholesterol is elevated, not sure of the figure but they said higher than what they would like but not a major concern. pretty much what happened to me is felt awful probably from the hypo? had blood test which incidentally found kidney issue and while looking into this found the hyporthyroid issue, I had put some weight on earlier this year about 15-16lb but have lost about 5-6lb of that in the last 6 weeks but not changed anything diet wise which I had put down to giving up smoking then thinking it maybe evening out a bit?. I have only been on levo for 7 days but noticed constipation easing, maybe a coincidence?


Just an update for any one searching link between kidneys and thyroid, after some very interesting chats with 4 doctors who said they knew of no link I gave them links to articles on thyroid making you kidney looking like failing, they dismissed this at the beginning until every appointment my kidneys recovered more and more like the reports said could happen, by the end I had 3 doctors and a student in the room with me discussing it, they said they had tested 4 more positive kidney-thyroid links after what I had been telling them, the snr doctor had looked into the connections and found up to 1953 these checks were taking place.

Anyway few years later kidney is fine and if feel 100% free of hashis.


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