Ft3 level estimation

[Sybilla14]

Hi. I took Levo c.28 hours before and Lio c.9 hours before a blood test at 9.30am. Unfortunately the blood test timing wasn't great and I could not take the Lio 12 hours before. I took the previous dose of Lio at c. 4am and the one before the test at 12am i.e. earlier than my dose would normally be.

I think I need to add 20% on to the ft4 reading to get the correct level at 24 hour from dose. Where would my ft3 have been at 12hours from dose based on the reading I have at 9 hours after dose, please?

Thank you.

[SeasideSusie Remembering]

Sybilla14

You don't have to worry. You will get a normal result for circulating hormone when the last dose of T3 is 8-12 hours before the blood test. The fact that you took your dose 9 hours prior to the test is nicely within the window.

I wouldn't worry about your FT4 either, it's a little over the 24 hours but not too much.

[Sybilla14 in reply to SeasideSusie]

Thank you SeasideSusie. My ft3 was over range at 8.43 (3.2-6.8) so do you think I'm okay to stay on this dose? I reduced by 6.25mcg a couple of weeks ago to try it and I was feeling very bad then.

[SeasideSusie Remembering in reply to Sybilla14]

Sybilla

My opinion is that your FT3 is too high and it's recommended to stay range, there could be a little leeway with it slightly over but I would say yours is too much. That's the sort of result one would expect to see if you'd taken your T3 just before the blood test.

What was your FT4 result?

[Sybilla14 in reply to SeasideSusie]

My ft4 was 19.5 (12-22) which was the same as it was before I took the Lio. My ft3 was 4.5 (3.2-6.8) then.

[SeasideSusie Remembering in reply to Sybilla14]

Sybilla

Have you tried reducing your Levo? When on a combination of Levo and T3, the Levo often reduces when taking T3. Some of us need our FT4 quite high in range, but some of us do equally well with a lower FT4. You had some conversion when on Levo alone, not brilliant admittedly, but some, a bit like mine. So if you reduced your Levo you might find your FT3 reduces too. It's a long, frustrating journey tweaking doses of both Levo and T3 to get the right balance.

[Sybilla14 in reply to SeasideSusie]

I was thinking just that. I'll try to reduce my Levo by 12.5mcg and see where that takes me. I've been quite sensitive to Levo dose changes before so I may know if the reduction works for me or not. I worry reducing the Lio would be hard after the recent 'trial' I did.

Thank you very much for your kind help!

[SeasideSusie Remembering in reply to Sybilla14]

You'e welcome. I hope you can sort out the balance that's best for you.

[greygoose]

Do you have Hashi's?

[Sybilla14 in reply to greygoose]

Yes I do.

[greygoose in reply to Sybilla14]

Then that could be why your Frees were over-range. Do you have a previous result on the same dose?

[Sybilla14 in reply to greygoose]

It's the first test since I added Lio to my Levo in January. I kept my Levo at 150mcg. I slowly increased to 19mcg and dropped down to 12.5mcg for 13 days in June (think it was on your recommendation to see if my tremors reduce) but I felt very rough on that dose. I went back to 19mcg but delayed taking from 12-1am to 3-4am and started to feel markedly better - I think that my stomach takes a long time to empty as we eat quite late. Or there's another reason the timing helped.

My ft4 is almost the same as it was on Levo only (think it was 20.7 in same range).

[greygoose in reply to Sybilla14]

I would be very surprised if it were that low dose of T3 that caused your FT3 to go so far over-range. Far more likely to be the Hashi's.

[Sybilla14 in reply to greygoose]

Thank you Greygoose. That's interesting. My symptoms do tend to swing, I can feel okay for a while and then suddenly have a turn so I did wonder if I need to start a more restrictive diet. But it's difficult to work out what is causing anything.There are so many moving parts to this disease it's a full time commitment to try and control it...

Would you say reducing Levo is a good idea or should I wait and retest in a bit first?

[greygoose in reply to Sybilla14]

I would say, stop the hormone completely for a couple of days, until you start feeling hypo, then start again on the same dose and retest in six weeks.