Years ago, we as hypothyroid patients due to any cause, noticed a phenomena we call pooling: T3 going high in the blood, thus not making it to the cells. We noticed this when, in trying to raise T3 in our treatment, it was causing heart palps, or a higher heartrate, or any hyper-like symptoms. In some, it can mean a high FT3, and low FT4. Check out the information below and see what you think. Also share the information with your doctor ~Janie, hypothyroid patient and site creator.

Pooling means your free T3 isn’t making it well to your cells, and instead, is hanging out in your blood, going higher and higher as you raise your T3-containing thyroid medication, whether you use synthetic T3, or the T3 in a working desiccated thyroid.

Why does pooling happen?

Pooling, aka your free T3 going way too high (and the higher it goes, with accompanying hyper-like symptoms), seems to always be associated with having either 1) low cortisol 2) high cortisol and/or 3) low aldosterone, another steroid. Even midrange aldosterone is too low.

What are symptoms patients experience due to pooling, which pushes excess adrenaline as one raises a T3-containing medication?

They are individual. At first, pooling may not be recognized. But eventually, we can note a higher in the range Free T3, yet with continued symptoms. If on natural desiccated thyroid or T4/T3, we can notice a rising Free T3 with a low Free T4. As we raise, the most common symptoms are heart palpitations, a rising heartrate, and in some, anxiety. Some notice increased hypothyroid symptoms, which can include fatigue, depression, etc. Others notice the “hyper-like” symptoms such as anxiety, panicky feeling, jittery, shakiness, heart palps, higher heartrate, higher blood pressure, etc.

What causes pooling and what have patients done about it?

For most hypothyroid patients, the causes are pretty clear: stressed adrenals, which can include low cortisol, or high cortisol, or a mix of both, or even low aldosterone. So we realize any of those will need to be discovered (saliva testing for cortisol; blood for aldosterone) and treated before we can comfortably raise T3 in our treatment, plus truly get out of our hypothyroid state.

What testing do we do?

We find that the best test is NOT blood cortisol, which doctors will wrongly recommend. Instead, we order and do a saliva cortisol test, which you can do on your own, and is measuring that what is available and unbound. Blood is measuring what’s mostly bound and unavailable. And blood results do not always fit what our symptoms tell us. Plus a blood cortisol test is only at ONE TIME, and you miss what’s going on at other times. You can click below to order a saliva cortisol test.

When you get your saliva results

When you get your lab results back, compare them to the information on the lab values page. The latter is based on where patients fall who don’t have a problem. This may be information you’ll have to teach an open-minded medical professional. You will also need aldosterone tested via blood.

Are pooling and a high Reverse T3 the same thing?

No, they are two different issues. Read about rising RT3 here.

If I have no symptoms of pooling, yet it’s very clear with labs, do I not have a problem?

Patients still see a problem and need to treat the pooling, we’ve discovered, which is usually always about a cortisol issue or low aldosterone.

My doctor wants me to move back over to T4-only, claiming the T3 in NDT is just too much for me, thus why it’s high. Is that the solution?

Not at all!!! Doctors don’t get “pooling” or what causes it!! So they tend to send us back to an inadequate treatment with T4-only. But we found it’s NOT the solution and only makes the reasons for your pooling WORSE–stressed adrenals.

What is the treatment solution for pooling, say patients?

REMEMBER: this page is simply information based on all we’ve learned. It’s not telling you what to so. See if you can guide and work with a doctor.

First and foremost, patients report learning over the years to treat the causes of pooling by ordering a 24 hour adrenal saliva test, since either low cortisol, or a mix of highs and low, or mostly highs can do this. A cortisol test for us is never blood testing! Blood is measuring mostly bound, unusable cortisol. Saliva measures what is useable.

We CAN use blood to test aldosterone, another cause of pooling.

Treatment is then explained in Chapter 6 of the updated STTM book, aka STTM I, which you can see here and has the blue gray cover. Note: Be careful when ordering from Amazon as there is a dishonest seller there who sells you the former version. The new version has many updates.

In the meantime…

a) Some do fine temporarily keeping the pooling as it is, as long as we don’t have symptoms…but we’ve learned repeatedly that we still need to discover and treat the cause of the pooling. Discovering it is via the saliva test. Treating it is by treating the cortisol problem, as well as potential low aldosterone, which is explained in chapter 6 of the STTM book. This is information to use with a doctor.

b) Some, because of symptoms of the pooling end up lowering their T3 until any hyper-like symptoms stop. But we again learned we have to do the saliva test to see what needs to be treated, as well as aldosterone testing via blood. Without treating, we can’t raise a product with T3 to get out of our hypothyroid state.

c) IMPORTANT WARNING: We learned the HARD way to never start on cortisol treatment if we pooling, as it will cause that high level of T3 to RUSH into the cells like a son-of-a-gun and give horrible hyper.. We learned we have to lower that high FT3 before starting on cortisol for any low cortisol issue as discovered via the saliva test. Again, Chapter 6 in this book.

d) For those who go down on their T3 containing thyroid meds to lower symptoms of pooling due to a cortisol problem…patients have reported going down by half or more, allowing the pooled T3 to fall, and which can happen within a week if lowered enough. Some are able to go back up in teensy amounts as long as pooling doesn’t start again. Treating the cortisol problem is then paramount, patients report learning. If symptoms of hypo return, patients may add smaller increments of T3. But it’s important to remember that your T3 will pool again if you haven’t treated the reasons for it, which is about a cortisol problem, so judicious use of the added T3 is important.

REMEMBER: this is just information as learned by patients. Work with a doctor.

Bottom line

We’ve learned how very important it is, before raising a working NDT or T3, to see where our adrenals stand using this: We use saliva cortisol testing, and compare the results to the Lab Values page, then treat if we see a problem. We test aldosterone via blood. Treatment of a cortisol problem is completely explained in chapters 5 and ESPECIALLY chapter 6 of the updated revision STTM book. Teach your doctor.

This research explains the “altered interaction between T3 and cell receptors:

**Read more about IRON AND CORTISOL. It’s important. 


Important note: STTM is an information-only site based on what many patients worldwide have reported in their treatment and wisdom over the years. This is not to be taken as personal medical advice, nor to replace a relationship with your doctor. By reading this information-only website, you take full responsibility for what you choose to do with this website's information or outcomes. See the Disclaimer and Terms of Use.