Ndt right dose and still tired in afternoon?

Hi all. Anyone taking ndt and still get a bit sleepy in the afternoon? Felt like I was going over at 1.5 grains and test results were tsh 0.12 and t4 13.6 so seems right move to drop back to 1 1/4. Ferritin and vit d now ok (ferritin 87.8). Was expecting when I was medicated to right level I wouldn't be tired. Not like pre diagnosis in that I can fight it now and it goes away (I used to just collapse into bed for an hour). Any thoughts appreciated (and t3 results not back yet). Thx. 😆

17 Replies

  • Olsbird,

    Your FT3 result will show whether or not you are optimally medicated. Please include the lab ref range so members can interpret the FT3 result.

  • I have a question in this context. We are often advised not to take any medication for 24 hours before going to the lab. So far, I have always followed that advice, and my FT3 levels end up mid-range 24 hours after taking NDT. If I would go to the lab an hour or two after taking my meds, they would most likely be at the top of range. FT4 is unlikely to be affected one way or the other, as far as I know. So, would it be a good idea to take my usual dose of NDT before going to the lab, to make sure my FT3 levels are optimal? I'd think they are, as I feel very well on my current dose and felt slightly hyperthyroid when I tried to raise it, but I have been wondering how to interpret mid-range FT3 levels 24 hours after taking NDT? I'd also imagine that FT3 levels at top of range 24 h after latest dose would indicate they were twice as high the day before, meaning very out-of-range...?

  • Anna69,

    If you leave 24hrs between last dose and blood draw and extrapolate the FT3 result by +20% that will be your normal estimated FT3 level.

    Otherwise, arranging your blood draw 8 hours after your last dose should be long enough for T4 and T3 to have stopped peaking in your blood and will give you your normal circulating levels.

  • Thanks a lot, Clutter!

    I found the following information on the STTM (about how to interpret labs):

    "If you have low FT4 and a mid-range or slightly higher FT3, it usually means the T4 is converting like mad to give you the FT3 you do have, which means hypo".

    I have been on Thyroid-S for the last few months and doing really well on it, compared to how I did on Armour and Erfa before that. I feel stable on it and have no hypo or hyper symptoms.

    I have really been hoping Thyroid-S would turn out to be the right NDT drug for me, as neither Armour nor Erfa seem to work optimally anymore...and no other brands of NDT are available in Belgian pharmacies. Of course, I could always find a pharmacy abroad shipping for instance WP or NP Thyroid even if the prescription is for Armour or Erfa (after all, they are supposed to be bio-identical) but, given the price of NDT drugs in most countries, I'd really like Thyroid-S to work for me...so far, it's the best thyroid drug I have tried, and I have tried synthetic combo drug Novothyral (T3+T4) and Thyrogold in the past, as well as T4 only.

    OK, now I am going to reveal my ignorance, but I tried to use the formula you provided to get an idea of my actual, circulating FT3 levels on the day before the test (since I left 24 h between taking the meds and having labs). My FT3 levels were 2.9 pg/mL (ref 1.7-3.7). I don't know if I used the right formula, but the result I got indicated that my circulating levels the previous day would be 3.4...so pretty close to upper normal range.

    The FT4 levels are more difficult to understand, though. 0.8 ng/dL (ref 0.7-1.5), so at the very bottom of range, on 5 grains of NDT daily which contains 190 mcg of T4. On 200 mcg of L-Thyroxine daily (and no T3), my FT4 levels were 1.4, so at the very top of range...I'll never be able to figure this one out.

  • Anna69,

    FT3 2.9 + 20% = 3.48 which is in the top third of range.

    FT4 is usually low when taking NDT.

  • Thank you so much:-)) That explains why I feel well on current dose, and slightly hyper when raising it...

  • Blood tests when on NDT don't correspond to the results when taking levothyroxine alone. NDT is the original thyroid hormone replacement and was introduced in 1892. Levo and blood tests were introduced together around the late 50's/60's. .

    NDT doesn't correlate to the tests for levo as it contains more than T4 (T3, T2, T1 and calictonin), levo is only T4 and its job is to convert to T3 and doesn't always do so efficiently.

    Adjusting NDT is until you are 'symptom-free' is correct and you increase about every 2 weeks till you are symptom free. Blood tests are irrelevant unless you take too much but you'd reduce them anyway with the unpleasant symptoms. 1.4 grains is around 150mcg or less of T4 so isn't a high dose. Many take doses up to about 5 +. I think the average is around 3+.

    (I am not medically qualified but have hypothyroidism but I am well now).

  • Thx. Yet to get t3 test. Long story which started with "what is ndt, I have never heard of it" from my gp. Sigh sigh sigh. I don't think I can take any more ndt as feeling over at 1.5 grains but maybe me again as hit a levo ceiling at 25 mcg and anything higher sent me overactive. So maybe now hit my ndt ceiling....

  • Undermedicated and overmedicated symptoms can be very similar. I doubt you've reached your maximum dose at 1.5 grains. If you can't tolerate more it's likely your ferritin levels are on the low side. To know what's going on you could do with a ferritin and FT3 test. You can always have them tested privately.

  • Thank you so helpful

  • It seems many if not most patients end up with a suppressed TSH when taking an optimal dose of NDT. You can never go by the TSH alone to judge whether you need to raise or lower your dose, as others have pointed out, as you cannot expect your lab results to look like they did when you were on T4 only.

    To give you one example of this: when I was on T4 only, my FT4 levels were at the very top of lab range. Now, on NDT, although I get as much T4 every day, my FT4 levels have dropped significantly and are now at the bottom of range. Despite this, I am not hypo at all; on the contrary. At one point, I raised NDT slightly in an attempt to raise my FT4 levels, but soon ended up with hyperthyroid symptoms and had to cut back. Someone here pointed out that when on NDT, your FT4 levels are bound to be lower as there is less need for the body to hold on to all that T4 (now that it's getting direct T3 along with T4), and it makes sense to me.

    This means that when on NDT (or other meds containing T3), you should pay more attention to your FT3 levels, and disregard the TSH. As long as you don't display any hyper symptoms, you are unlikely to be overmedicated, no matter how low your TSH drops.

  • I am on 2 grains and still have to have an afternoon siesta!

  • Thx. Did your doc think this was ok - is that you were still sleepy?

  • My endo does not care as long as I do not add tohis drugs bill! I have tried increasing but it causes me problems.

  • By problems do you mean hyper symptoms? Feel like I've hit my ndt ceiling and it's a different ceiling to what I think I need. Wondering if maybe adding some t3 could help given I struggled with more than 25 mcg levo ..... I can't bear this tiredness😣

  • No, it just doesn't help.

  • My results are now pretty good, but that sofa shouts very loudly at around 4 in the afternoon. I think there is a magnet in it, as I find I am drawn towards it, and then cannot get away without a "power nap". I blame the cat, as she likes a snooze on me!

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