What’s the right term for medication benefits wearing off? Specifically when there has been an initial improvement in health and benefits felt, then after a few weeks these wear off again and you’re back to square one and then likely need a dose increase?
I’ve been on T3 for 7 weeks now and after some rough side effects definitely saw an improvement in my lethargy and fatigue levels. Now it’s wearing off and I’m back to needing afternoon naps again. What would be the right term to use to explain this initial bump to my endocrinologist? I had the same thing when I started Levothyroxine- saw benefits that then tailed off and never returned despite dosage increases.
I hope this makes sense and someone knows what I’m going on about! Thanks in advance
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Confused22
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Although it not the case with thyroid replacement - the affect is not reduced it’s that the body adapts to the dose given, the TSH changes - usually lowers, and by the time the new dose settles it’s not “topping up” levels as it did initially - it’s partly replacing it and you need a dose increase until you reach the right level.
Ah thank you, that makes sense the way you’ve explained the course the medication takes. Will I ever reach that sweet spot of the right amount of medication where my body doesn’t then adapt? Or is that ultimately the aim - to effectively replace with enough medication so the thyroid switches off and doesn’t need to work at all any more?
Fully replacing the function of the thyroid isn’t the aim but sometimes that end up being the case as the thyroid can maintain the necessary levels.
Once the levels settle to the right amount for you & thyroid not struggling to keep up - & your symptoms resolve then you have got to the right point.
While TSH is in range & not below it - the pituitary is stimulating the thyroid and it will be producing it own thyroid hormones.
When taking T3 the TSH does often go very low before adequate FT3 levels are met, but doctors expect the TSH to be in range, so it’s a case of going very slowly & testing FT4 & FT3 levels.
While TSH is in range & not below it - the pituitary is stimulating the thyroid and it will be producing it own thyroid hormones.
That’s so interesting, I had never really considered that, thank you. I feel into the medical world’s trap of thinking low tsh meant thyroid itself switching off but of course we know tsh is a pituitary hormone so that can’t be the case. Lightbulb moment there, thank you!
Thank you for taking the time to explain it further to me, it’s a huge help to my understanding and feeling better prepared for my next appointment, I really appreciate it
That is the normal course of events - with both levo and T3. But, I really don't know if there is any medical term for it. I've never heard of one, so I shall be interested to see if anyone comes up with something.
Early days...after 7 weeks your body is just beginning to adapt to the addition of T3!I'm not sure that there is a medical term for a post increase slump,
Other than, as Oliver Twist asked, "May I have some more please?"
It happens because...
Initially the body has benefitted from the increase but as that settles....
a) it will become evident that more is require....a slump.
Or
b) you will feel well.... if the dose is adequate.
Your body will soon let you know if something is wrong!
A well informed endo should know this!
I need high dose T3-only to function and initially felt as you do...and at that point had little knowledge about T3 dosing
Sometimes you can even feel worse!
It can be quite a challenge.
It's normal but it took me time to learn and work out what was going on.
Don't worry about it...just stick with it.
You need to very slowly (6/8 week intervals) raise the T3 in tiny doses (5 or 6.25 mcg...a quarter, depending on strength of tablet - 20 or 25mcg)
For reference, keep a note of dose and symptom changes
Hopefully you will fairly soon reach your therapeutic dose....and feel well!
Your endo may bang on about TSH levels but you need to focus on FT4 and FT3 instead....especially FT3 the active thyroid hormone.
So long as your FT3 lab remains within the ref range you will not be overmedicated.
Don"t allow/make dose changes on the basis of TSH alone...that is asking for problems.
Thank you for your time and reply DippyDame, that’s all incredibly helpful. And I like your term ‘post increase slump’, that sums up really well what I was trying to explain. Thanks brain fog!
Yes, you’re right; I went back to my Gp to ask for another blood test yesterday but she said 7 weeks wasn’t long enough and to wait another 6/8 yet. I’m just so impatient and know it’s not helping as much any more and want to increase asap to get better as quickly as possible!
For reference, keep a note of dose and symptom changes - this is excellent advice, thank you I shall do that
Thank you for all of your help, it’s very much appreciated
I would say 7 weeks is a good time for blood tests to see what's going on but it sounds like your GP is asking you to wait because T3 has great hepatic influence and raises binding transporter carriers secreted by the liver. SHBG usually only raises in the presence of high T3 but if you have been T3 deficient for some time the liver can become over-sensitive to any T3 introduction.
If reduced 'frees' evidenced by TFT's that match symptoms don't recover you may need a dose raise (but not necessarily T3). If this scenario was to happen/repeat after thyroid hormones have been optimised you may need to look at oestrogen levels. However, hopefully things will level out and you will feel better.
I don't know the term but DD's 'post increase slump' sums it up nicely.
Thanks radd, I was frustrated at having to wait but what you’re saying does placate me a little. So regarding shbg, should I be getting that tested as well at the 3 month mark? It’s not been selected for testing on my next bloods form. My previous SHBG results were:Dec 2020 (unmedicated) 50.1 nmol/L [32.4-128]
Dec 2021 (100mcg T4 only ) 68nmol/L [32.4-128]
Interesting point regarding oestrogen - again have had that tested years ago and was in range (August 2020 result was 184 pmol/L [can’t find the range with the results but think it’s Follicular phase 45 - 854]) but I now have symptoms indicative of low progesterone and even oestrogen dominance. Why would that be affecting my thyroid? Or does oestrogen dominance cause symptoms like hypo symptoms and one can be confused for the other?
Thank you so much for all of your time and help with this
Yes, given your symptoms I would want SHBG tested to eliminate this problem otherwise you risk masking your true optimised thyroid hormone levels and unnecessary raises may overshoot your sweetspot.
Your next lot of TFT’s will be very informative as to whether you still have a genuine deficiency of T3 or enough that isn’t working due to other causes. You don’t want to get into that scenario of taking T3 higher & higher never relieving symptoms for any length of time because you have actually missed your sweetspot and other causes are now muddying the waters.
It’s great you have previous baselines to compare with. SHBG transports oestrogen, DHT & testosterone. If oestrogens (or the others) are elevated, then SHBG will follow suit and vice versa.
Oestrogen is known to increase TBG that carries thyroid hormone around the body. When more oestrogen travels through the liver than is bound to SHBG, TBG will raise and ends up binding too much thyroid hormone. Our thyroid hormones need to be 'free' to become active in the cells.
The fact you have benefited from introducing T3 is very positive and annoying symptoms are reoccurring but you just need to be patient. Hormones can never be rushed to reach their final efficacy but if this were me I don't know if I could wait another 6-8 weeks. It seems excessive. Why don't you do some private test if funding allows?
Just read previous post and I thought you had introduced 10mcg T3 too quickly and judging by your previous TFT's you appeared a good converter and I questioned your need for T3.
Given your difficulties in introducing T3 I would definitely be organising TFT's asap just to assess levels haven't gone too high. Ironically going too high with thyroid hormone sometimes means less works.
Thank you radd, that is all so helpful and fascinating, thank you for being so thorough in your explanation. When I see the endocrinologist and tell him my symptoms he just sniffs and says it’s not a thyroid problem. But won’t actually SAY WHAT HE SUGGESTS IT COULD BE. He says he could give me ‘a list as long as his arm’ of conditions that could be causing my symptoms but won’t actually name any. It’s infuriating, but your explanation of different hormones having an affect at least gives me a starting point, thank you.
Private testing is a potential, but at this point I’m thinking ignorance is bliss! I know the medication isn’t helping as much any more and if tests show my numbers to still be ‘off’ then I’ll have to wait the 6 weeks till my endo appointment to get the medication altered anyway, and just be stewing till then that I need a dose change, so thinking now I might as well just wait!
Drs usually use the word 'tolerance' when referring to the fact that the body has got used to a drug and now you need more of it to achieve the same effect.
By Shalini S. Lynch, PharmD, University of California San Francisco School of Pharmacy
Last full review/revision Aug 2019| Content last modified Jan 2020
Tolerance is a person's diminished response to a drug, which occurs when the drug is used repeatedly and the body adapts to the continued presence of the drug. Resistance refers to the ability of microorganisms or cancer cells to withstand the effects of a drug usually effective against them.
Thanks, nice clear article. The conclusion is particularly important. If you develop tolerance then the dose can be increased, but if resistant you need a different drug. I would have thought that for patients on levo there is a likelihood of tolerance developing in the early days particularly, when the initial dose needs to be increased. Long term once the right dose is found the patient should remain stable unless something changes in the patient (eg weight gain or developing another illness), or the drug ingredients change. As levo is a hormone I would guess resistance shouldn't happen? ( more likely seen in a drug to treat an illness, such as antibiotics). Although a reaction to a particular form of the drug (or brand) could occur?
Thank you helvella, thats an interesting and specific distinction between the two terms of tolerance and resistance. I think in my case it will be the former but blood results may show otherwise. That’s really helpful of you, thank you again
Hi Confused. I think what you might say is that you've developed a tolerance to the current dosage and you are no longer feeling any great benefit such as you did when you started. You feel you now need an increased dose to get some relief from your symptoms.
It takes 3 months for thyroxine (levothyroine) to get into your system and your brain and hormones to work it all out and settle. TSH which is not really a gold standard for thyroid.. should be 0.2 -1.5 (2.5 max!) Find your optimal level.Don't take your levo on the morning of your blood test as it will give false results.. and remember if you have a test in the morning your thyroid has just released and it will be higher.. we get tired in the afternoons.. but docs don't test then!
What you say is true I think, three months to get a real difference. It feels like a very long three months when you're not sure your dose is right though!
Thanks ThyroidalLinda - is it the same 3 month wait for Liothyronine (T3)? And yes absolutely, shame they don’t test just as I’m crashing in the afternoon to get a proper snapshot of what’s going on!
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