Results

[redted]

Hi can someone explain these results for me,I have had an underactive thyroid for at least two yrs,started on 25 now on 75 had blood taken 8 weeks ago and this is the result,first printout I have ever had.

Serum free T4 level. 20pmol/L. 9.00-25.00pmol/L

Serum TSH Level. 0.72 mix/L. 0.30-5.00 miu/L

I am on Levo.

[Clutter]

Redted, you look to be optimally medicated with TSH just below 1.0 and FT4 just a smidgeon off the ideal top 75% of range.

[redted in reply to Clutter]

Oh that's great,thanks so much,got to admit I do feel better than I did 12 weeks ago, 😄

[Clutter in reply to redted]

Redted, that's good to hear

[redted]

I asked the doctor if I should take my levo at my normal time of 6 am,and she said yes as it takes days to get the levo into the system,so it would take a few days for it to drop,my blood test was at 10-30 am.

My symptoms were dry flaky skin on my lower legs,a dazed feeling most of the time,tiredness,and a depressed feeling ( which I still have) but I am awake and up at 6am every morning,I keep myself busy,so I feel very sleepy by 10 am,I am 71 yrs old so expect to get weary.

[helvella Administrator in reply to redted]

The peak effect of a levothyroxine tablet on blood FT4 levels occurs approximately TWO HOURS after taking the tablet. Not days...

Bear in mind that the peak is a sort-of false peak which only occurs because you are taking a single dose a day (well, most people on levothyroxine do that).

Secondly, there is a peak of T3 (from conversion of the levothyroxine in the tablet), approximately TWO DAYS (that is, 48 hours) after the levothyroxine tablet.

(All the above can vary depending on lots of factors, but they are probably acceptable as a first-pass to think about things.)

[redted in reply to helvella]

Thank you I am saving your posts so I can mention the info the next time I see my Doctor.

[redted]

Oh this is interesting,I will not take my levo before my next blood test,thank you.

[greygoose in reply to redted]

Don't eat, either, that lowers the TSH, and you want it as high as possible. Get it done as early as possible in the morning - 10.30 is too late, the TSH will have lowered by then - best about 8 o'clock. So, in reality, your TSH is probably not so good...

[SlowDragon Administrator]

Most of the endocrinologists I have seen recommend trying taking thyroxine at bedtime rather than early morning. This certainly helped me.

The theory apparently is that it takes longer to digest/absorb at night and you might get better uptake. Still need to avoid food at least an hour before you take thyroxine. So good reason to avoid those late night snacks!