How to Find the Right Thyroid Hormone Dose

If you’re not feeling well, there is a good chance you suspect a thyroid problem as the cause.  Thyroid problems are common and can certainly be problematic.  However, it’s also important to have a balanced understanding of how to navigate your thyroid health.  Let’s discuss one important aspect of thyroid health – a reasonable approach to determine your optimal dose of thyroid hormone.

Dr. R’s Fast Facts

  • Initial dosing is usually based upon body weight (and other medical conditions)
  • After a number of weeks, TSH and fT4 can be retested to refine dose
  • After allowing a few dose adjustments, one of two problems may be occurring
    • Your labs are not normal = likely absorption problem
      • Fix your gut
      • Consider liquid form of thyroid hormone
    • Your labs are normal, but you do not feel normal = symptoms are likely not due to thyroid hormone imbalance and are coming from inflammation (often in the gut)
      • Fix your gut
      • Consider trial of T4 with T3 medication

How to Find the Right Thyroid Hormone Dose

Dr. Michael Ruscio: Hi, this is Dr. Ruscio, and let’s discuss how to find the optimum dose of a thyroid hormone.

If you’re not feeling well and you’ve been doing any research, you’ve likely come across thyroid as a potential culprit. And if thyroid is a problem, then you may have been recommended to be on thyroid hormone medication. So let’s discuss an easy hierarchy or an easy series of steps you can work through, either on your own or, hopefully, in conjunction with your doctor, to determine what your ideal dose should be, while also at the same time not getting pulled into any frivolous or unneeded recommendations to really help guide you through an efficient process of determining and establishing what your ideal dose can be and how to sort out where any problems that are thwarting you from finding your ideal dose may be coming from.

I made a little list for you, and I’ll put it up here on the screen. Number one, remember the initial dosing is usually based upon body weight and other medical conditions. So if you’re initially recommended to be on thyroid hormone, it is usually based upon body weight, and you want to give a little bit of time for this to take effect. So don’t expect day 2 or 3 or week one onto thyroid hormone for the first time for necessarily all of the improvements to be realized.

But when we move to step 2, after a number of weeks, TSH and free T4 can be re-tested to refine dose. Now, what you may find is after a number of weeks, you’re feeling only a little bit better. And when you re-test, you notice that your thyroid hormone levels, your blood work, is not yet normal. So you work with your doctor, and you tweak the dose, and you repeat.

And eventually, you’ll come to likely, step 3, which is after allowing a few dose adjustments, one or two problems may be occurring. So for some people, they’ll feel fine. Their levels will be normal, and the hierarchy or the discussion ends there. But for everyone else, you’re likely going to fall into one of two buckets. So here they are.

Your labs are not normal. And this likely equals an absorption problem. Now remember, this is after you’ve allowed for a few dose adjustments. So after you’ve allowed for a few dose adjustments and you haven’t gotten to a normal level, then it may be an absorption problem. And here are some things that can underlie that. One, it may be your gut. And this is sometimes is overlooked. But remember, to have consistent levels of thyroid hormone in your blood from the medication, you have to consistently be absorbing that thyroid hormone medication through your gut to get it into your bloodstream.

And it has been documented that finding the appropriate dose for those with gastrointestinal problems, like IBS, ulcers, H. pylori infections, can be challenging. So the problem here may actually not be your thyroid. The problem may actually be your gut.

Or item two, consider a liquid form of thyroid hormone. Some studies have been done with a thyroid hormone known as Tirosint in patients that have impaired gastrointestinal absorptions–ulcers, H. pylori, IBS–and they’ve actually shown the ability to have a much more consistent dose and feel better when they’ve put patients with impaired gut absorption on a liquid form of thyroid hormone. So that’s very important.

Now, you also may be the other bucket, which is, your labs are normal, but you do not feel normal. And I’m talking the lab ranges according to your conventional lab ranges. So we can keep it very simple for the purposes of this hierarchy. We don’t necessarily need to get involved with these highly meticulous or narrow lab ranges. If your labs are within the normal range of your conventional labs, but you’re not feeling normal, here is what you should do next or consider next.

The symptoms here are likely not due to a thyroid hormone imbalance, but your symptoms are likely coming from inflammation. And oftentimes inflammation can, again, occur in the gut. So a couple of things to consider there. One, fix your gut. Two, consider a trial of T4 with T3 medication.

Okay, now here’s how this plays out. Sometimes you can be on thyroid hormone medication that can get your levels into the normal ranges, but you still don’t feel well. That may be because there is not a problem in the thyroid any longer or with thyroid hormone levels. The problem is actually coming from your gut, and that’s causing symptoms that look like hypothyroidism. They look like a thyroid problem, but it actually is not. Or you may be someone that just quite simply feels better on a T4/T3 combination medication. So you may be in the normal range, but you may not be on the ideal medication for you.

And there have been a few studies that have found about 35% of patients prefer a T4/T3 combination medication. This may be Levothyroxine paired with Cytomel. Or it may be something like Armour Thyroid or Westhroid or what have you. One of these T4/T3 combination medications. And only about 15, 20% of patients preferred a T4 alone medication like Synthroid or Levothyroxine.

So the answer here may actually be a quite simple one, not requiring you to do copious testing and get a very analytical report on all the different fractions of thyroid hormone, which I’m open to and sometimes recommended, but probably not needed. The solution here may be a simple one. If you work through this hierarchy, your lab work is within the normal range, and you’re on a T4, you may simply achieve the benefit that you’re looking to achieve in terms of your symptoms by simply switching to a T4/T3 combination medication.

Now, this is important to keep in mind. Let’s say you’re working with your GP or your endocrinologist. On day one, if you ask them to put you on a T4/T3 combination medication, you may get some pushback, which is understandable. However, if you’ve work through this hierarchy, you’ve humored your doctor, you’ve allowed for a few dose adjustments, you’ve then looked into your gut health and you’ve done all these things, now you’re in a position where you’re most prone or most apt to be a candidate for T4/T3 combination medication.

And you’re at a very leveraged position to work with your doctor and say, “Listen, we’ve gone through all this together. I’ve kind of tried it your way to some extent and now I’d appreciate it if we could do a short trial of a T4/T3 hormone medication and see if I feel better.” It’s very reasonable. And in my opinion, if your doctor does not want to humor you there, then you may want to shop around for another doctor.

Now, there’s also something else to be cognizant of, which is sometimes when people go on these T4/T3 combination medications, they actually may feel a little bit worse, a little bit jittery. So it’s not to say that this is a panacea and it will work for everyone. And this is where your doctor may have a little bit of trepidation, because sometimes the addition of T3 can cause a little bit of anxiety, jitteriness, racing heart, palpitations, insomnia. That’s much more rare. Remember the study I mentioned a moment ago found that 45% of patients prefer T4 with T3, whereas only about 20% of patients preferred T4 alone. That’s just one study, but it certainly was noteworthy.

So coming back to this hierarchy, work through this if you’re not feeling well. And this has a very high probability of producing success. Now also, sometimes resolving a gut issue is a little bit easier said than done, especially if you don’t have a lot of resources. I’m happy to announce that I’ll have a book out late 2017, early 2018, that will give you a self-help guide for optimizing your gut health if you’re in need of resources there. But working through this simple hierarchy can be very helpful in preventing you from doing unneeded testing and treatment for what may not be a thyroid problem.

And I just make that note of caution, because there is a lot of information on thyroid on the internet. Some of it is good. Some of it is just marketing, and they can pull you into unneeded testing and treatment that ultimately will not work, and I want to try to prevent you from doing that as much as possible.

So this is a simple hierarchy that is evidence-based, that is effective, and that is reasonable, and should help you be able to feel better and sort out if your symptoms are coming from your thyroid or maybe not coming from your thyroid, or potentially coming from malabsorption or a gut problem.

So, this is Dr. Ruscio. I hope this information helps you get healthy and get back to your life. Thanks.

What do you think? I would like to hear your thoughts or experience with this.

Dr. Ruscio is your leading functional and integrative doctor specializing in gut related disorders such as SIBO, leaky gut, Celiac, IBS and in thyroid disorders such as hypothyroid and hyperthyroid. For more information on how to become a patient, please contact our office. Serving the San Francisco bay area and distance patients via phone and Skype.


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