Volunteer opportunity: Organizing Phoenix Rising articles
This section contains all the articles that have been published by Phoenix Rising over the years. As you will see if you browse here, some of the articles are outdated--either the research has been superseded or retracted or the article features an event or campaign that is now in...
Discuss the article on the Forums.

What should be the ratio of T3 / T4 supplementation ?

Discussion in 'Alternative Therapies' started by raghav, Feb 25, 2018.

  1. raghav

    raghav Senior Member

    Messages:
    278
    Likes:
    221
    India
    I am currently taking 150 mcg Thyroxine (T4) under supervision of an Endocrinologist for the past 18 years. I am getting Cytomel T3 tomorrow. So in what ratio should I take T3 and T4 ? 50 mcg : 100 mcg ? or should I start with 25 mcg T3. Endocrinologists in India have no idea or experience giving combination of t3 and t4. So what side effects if any that I should be on the watchout for ? Thanks in advance.
     
  2. BadBadBear

    BadBadBear Senior Member

    Messages:
    487
    Likes:
    665
    Rocky Mountains
    NDT is around 1:4. If you take too much T3, it suppresses T4 so its possibly problematic to use too much T3. As well, doses should be divided.

    My NDT has about 9 mcg T3 to 38 T4 per grain, and I divided my dose of 2.5 grains into 3 doses.

    Overall, my body still didn't use T4 and I have to be on T3 only.
     
    pattismith likes this.
  3. Learner1

    Learner1 Forum Support Assistant

    Messages:
    2,341
    Likes:
    4,025
    Pacific Northwest
    NDT is different.

    I'm on 137mcg T4 and 50mcg T3. I used to feel the same on 75mcg of each.

    It's not a one to one conversion. Instead of the extra 25mcg T3 I used to take, it took 2.5 times more T4. Other recommendations are 3x to 5x the amount of T3 to T4, which you'd going from T4 to T3.

    Ideally, your rT3 will be normal and your FT3 and FT4 will be midrange and you won't have hyper or hypo symptoms. Your TSH may be suppressed if you take T3, but just go by the other labs and how you feel.
     
    ebethc likes this.
  4. raghav

    raghav Senior Member

    Messages:
    278
    Likes:
    221
    India
    Thanks @BadBadBear and @Learner1 Labs in India dont offer rT3 test. Anyway let me start with 25:125 (t3:t4) and see how it goes.
     
  5. Learner1

    Learner1 Forum Support Assistant

    Messages:
    2,341
    Likes:
    4,025
    Pacific Northwest
    You will likely end up hyperthyroid. You might try going down to 75-100mcg of T4.
     
    Ema likes this.
  6. raghav

    raghav Senior Member

    Messages:
    278
    Likes:
    221
    India
    If I go hyperthyroid immediately my hr will shoot to 90. So I will know. Anyway will take what you said into account. Thx.
     
    pattismith, Ema and Learner1 like this.
  7. BadBadBear

    BadBadBear Senior Member

    Messages:
    487
    Likes:
    665
    Rocky Mountains
    That will be approx the equivalent of 225 mcg of T4 only. I would expect you will need to drop the amounts quite a bit to hit your current dose of 150 mcg of T4.

    I would start at 100 mcg T4, 10 mcg T3 which will be closer to your current T4 dose. But it will take weeks for your T4 levels to normalize on your new dose, which is a reason to go up slowly on your T3 dose and let your body adjust.
     
    Learner1 and Ema like this.
  8. CFS_for_19_years

    CFS_for_19_years Hoarder of biscuits

    Messages:
    2,246
    Likes:
    5,587
    USA
    Cytomel (T3) is about 4 times as effective as thyroxine (T4). If you want to introduce Cytomel slowly, you could start with the first combination:
    5mcg Cytomel + 130mcg thyroxine
    10mcg Cytomel + 110mcg thyroxine
    From here on you might think about taking half of your total Cytomel dose twice a day.
    15mcg Cytomel + 90mcg thyroxine
    20mcg Cytomel + 70mcg thyroxine
    25mcg Cytomel + 50mcg thryoxine

    See http://www.allocca.com/papers/Calculating_Thyroid_Replacement_Hormones.pdf

    I think the proper ratio for taking T3 and T4 is an individual thing. Most of my thyroid replacement comes from Cytomel because I can't convert T4 to T3.
     
    Learner1 and BadBadBear like this.
  9. Ema

    Ema Senior Member

    Messages:
    4,622
    Likes:
    6,668
    Midwest USA
    I take 75 mcg Tirosint (T4) and 5 mcg of Cytomel (T3) in the morning and 25 mcg Tirosing and maybe another 5 mcg of Cytomel in the mid afternoon.

    ETA: Whoops, forgot a dose!
     
    BadBadBear likes this.
  10. Learner1

    Learner1 Forum Support Assistant

    Messages:
    2,341
    Likes:
    4,025
    Pacific Northwest
    It's individual. That ratio doesn't work for me.
     
  11. ebethc

    ebethc Senior Member

    Messages:
    1,436
    Likes:
    1,045
    What's the typical dosage of T3, if there is one? asking b/c I've never heard that ratios are that important...
     
  12. Hip

    Hip Senior Member

    Messages:
    10,685
    Likes:
    17,570
    The normal average T4 to T3 conversion rate is 35.7%, or around one third. Ref: here.

    So if you are taking 150 mcg of T4, then you might expect that to convert to 50 mcg of T3 in normal healthy people.


    And if you are taking an extra say 10 mcg of T3, then you might consider subtracting 3 x 10 = 30 mcg from your T4 dose in order to compensate.


    Bear in mind that the half-life of T3 is around a day or so, which means that you may want to take your daily T3 dose in two divided amounts, to ensure you have reasonably uniform blood levels. The half-life of T4 is longer, around 5 to 7 days, which is why for T4 once daily dosing is fine.
     
    raghav likes this.
  13. BadBadBear

    BadBadBear Senior Member

    Messages:
    487
    Likes:
    665
    Rocky Mountains
    I think the half life does not predict the bioavailability. I need my T3 in 4 doses per day. If I take fewer doses, I have symptoms of too much T3 per dose, and I run out of T3 over night and wake with high adrenaline.

    I have heard of other people who can take a single dose in the AM or at bedtime and be just fine.

    Seems to vary quite a bit.
     
    raghav, Learner1 and Hip like this.
  14. CFS_for_19_years

    CFS_for_19_years Hoarder of biscuits

    Messages:
    2,246
    Likes:
    5,587
    USA
    These are all different ratios. None of them would work for me either since I rely mostly on Cytomel.
     
    Learner1 likes this.
  15. raghav

    raghav Senior Member

    Messages:
    278
    Likes:
    221
    India
    Thanks folks for the suggestions. I am also taking Testosterone gel 25 mg topical every morning. My endo wants me to go to the full dose of 50 mg of testosterone gel since my testo leveles are below that of the minimum of a 90 year old male. So this will also have to be factored in. Any way I will be testing thyroid and testosterone levels after a month or so.
     
    pattismith and BadBadBear like this.
  16. pattismith

    pattismith Senior Member

    Messages:
    1,457
    Likes:
    2,183
    @raghav , do you take TH to treat hypothyroidism?

    T3 should be taken three times a day, this is what showed up in this study by Pr Jonklaas (2016) (below)

    Her results (table A) match pretty well with what I noticed when taking T3 with non genomic effect starting an hour later and ended 9 hours after intake.


    Daily Administration of Short-Acting Liothyronine Is Associated with Significant Triiodothyronine Excursions and Fails to Alter Thyroid-Responsive Parameters

    [​IMG]


    in this study where they used T3 or T4 with three intakes per day, they found:

    "The dose of l-T3 was 0.57 ± 0.08 μg/kg · d, whereas the l-T4 was 1.68 ± 0.33 μg/kg · d with a microgram/microgram l-T3 to l-T4 ratio of 0.34 ± 0.05"

    which means the dose to achieve the same TSH result, was T4 daydose = T3 daydose/0.34= 3 x T3 daydose, which is the same @Hip quoted.

    By the way this study found that the effect of three daily doses of T3 has much more effects on many metabolic parameters (lipid metabolism) than T4.

    I noticed that Heart rates were not different (about 80 BPM at rest)
     
    BadBadBear likes this.
  17. Nine lives

    Nine lives

    Messages:
    49
    Likes:
    40
    I take AM base dose T4 50 mcg and divide Naturethyroid (preferred WP but slow coming back online) AM , 2PM, and 9 PM (1/2 a grain each time).

    Splitting doses helped lower my high SHBG somewhat. Paradoxically, dose just before bed helps with sleep.
     
  18. pattismith

    pattismith Senior Member

    Messages:
    1,457
    Likes:
    2,183
    @Nine lives
    if you look at table 2 in the study I quoted below

    https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3205882/table/T2/?report=objectonly

    you will see that 3 doses/day T3 increases less SHBG than 3 doses/day T4....

     
  19. Nine lives

    Nine lives

    Messages:
    49
    Likes:
    40
    Interesting since natural porcine thyroid has a lot of T4. Will check SHBG again in a couple of months. If still high, one way to go may be smaller T3 only doses.
     
  20. lnester7

    lnester7 Seven

    Messages:
    2,635
    Likes:
    3,828
    USA
    What?
    Do you mean T4 = 3 XT3?
     

See more popular forum discussions.

Share This Page