Why Some People Feel Worse on Thyroid Medication

Why Some People Feel Worse on Thyroid Medication

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The day finally arrives…

After weeks of research, symptom documentation, and lab tests, you’ve finally been diagnosed with a thyroid problem and your doctor has written you a prescription for thyroid medication

You are so excited to finally have an answer for the weight you’ve been gaining, the low energy you’ve been experiencing, your cold body temperature, your recent hair loss, and more. 

You start taking your thyroid medication each and every day and patiently wait for your symptoms to resolve only to be met with disappointment.

Instead of resolving your symptoms, you actually feel worse on the very treatment that is supposed to make you feel better.

Instead of having more energy, instead of losing weight, instead of growing your hair back, you experience the exact opposite. 

How can this be? How can you feel worse while taking thyroid medication even though it’s supposed to be the answer to your problems?

Well, it turns out there is an explanation as to why it happens and that’s exactly what we are going to discuss today.

Today you will learn…

  • Why some people feel worse while taking thyroid medication
  • How thyroid medication impacts your physiology
  • The long-term effects of prolonged thyroid medication use
  • And what to do if you are feeling worse on your thyroid medication

Let’s jump in… 


Foods to Avoid if you Have Thyroid Problems:

I’ve found that these 10 foods cause the most problems for thyroid patients. Learn which foods you should avoid if you have thyroid disease of any type.


The Complete List of Thyroid Lab tests:

The list includes optimal ranges, normal ranges, and the complete list of tests you need to diagnose and manage thyroid disease correctly!


How Thyroid Medication Works in Your Body

To better understand why thyroid medication can make you feel worse you first need to understand how thyroid medication works in the body.

Once you understand this simple physiologic process (1) it becomes easy to understand how it can become disrupted.

First things first:

Doctors only prescribe thyroid medication to patients who have low thyroid function. 

This means that anyone using thyroid medication is doing so because their own body cannot produce enough thyroid hormone on its own. 

This could be because your thyroid gland doesn’t work (2) or because your brain isn’t sending the right messages to your thyroid (3).

Where the problem is matters, but for the sake of this discussion, you just need to know that both problems result in the same thing: decreased thyroid hormone levels.

definition of primary hypothyroidism and secondary hypothyroidism

The thyroid medication that your doctor gives you is supposed to make up for that difference. 

But there’s a big problem with this approach:

Your body was designed to have what are called feedback loops (4) built into it. 

generic hormone feedback loop system in the body

These feedback loops help prevent your body from creating too much of any one hormone and from the negative consequences that this could cause. 

So when your doctor gives you thyroid medication (such as levothyroxine), it will have an impact on your brain via these feedback loops.

This happens because the body doesn’t know the difference between a hormone that it creates on its own or one that you are taking in a medication form.

Both types have the same impact.

The message that your thyroid medication sends to your thyroid gland is to reduce the natural production of thyroid hormone.

This effect is dose-dependent, so the more thyroid medication you take, the more profound an impact it will have on your body’s ability to create thyroid hormones.

This effectively means that you are replacing your body’s own thyroid gland function with the medication that your doctor is giving you. 

This is okay, though, because it wasn’t working right to begin with so how can it cause problems?

How Shutting Down Your Own Thyroid Can Make You Feel Worse

It’s actually quite easy. 

Let’s compare what the healthy thyroid gland does on its own versus what happens when you use thyroid medication to try and replace its function:

Consider these facts about the healthy thyroid gland:

This may seem a little bit confusing but consider this example to help it sink in:

Imagine that you are someone who has a thyroid problem such as Hashimoto’s thyroiditis which has damaged your thyroid gland. 

A normal healthy thyroid gland may produce something like 100 mcg of T4 and 20 mcg of T3 each and every day (this is just an estimate but it’s a fairly accurate number for the average person).

But because your thyroid gland has been damaged from Hashimoto’s, it’s only functioning at 70% of normal. 

So instead of producing 100 mcg of T4 every day, you are only producing 70 mcg and instead of producing 20 mcg of T3 every day, you are only producing 14 mcg. 

This is a problem and it makes you feel worse (you experience all of the symptoms of low thyroid as we discussed above). 

You go to your doctor and he/she provides you with a prescription for levothyroxine

Because of the feedback loops mentioned previously, the thyroid medication you are taking shuts down the normal production of thyroid hormone from your thyroid gland.

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Instead of producing 70 mcg of T4 and 14 mcg of T3 every day, which is what your unhealthy thyroid gland produced in this example, your doctor gives you a prescription for 100mcg of levothyroxine which contains 100mcg of T4 (7). 

And here’s where the problem begins…

As you take this levothyroxine, you are replacing the combination of T4 and T3 thyroid hormones with T4 thyroid hormone alone.


Even though your thyroid was not functioning optimally, it was still able to squeeze out 14 mcg of T3 every day.

But because you are taking levothyroxine, that production was shut off and replaced with 100% T4 thyroid hormone from the medication.

If you recall our previous discussion about thyroid facts, you will see why this is such a big problem. 

As I stated, T3 thyroid hormone is roughly 200 to 300x more biologically active than T4 and is the most powerful thyroid hormone!

In effect, the use of levothyroxine has replaced the most powerful thyroid hormone in your body with a much weaker version but at a higher dose.

This mechanism is why thyroid patients can feel worse on thyroid medication

It is actually this simple

Now the question becomes:

What can you do to fix this problem so that you actually feel good on thyroid medication? 

Fixing The Brain-Thyroid Connection

In order to feel better on thyroid medication, you must address the brain-thyroid connection. 

This brain-thyroid connection is usually referred to as the hypothalamic-pituitary-thyroid axis (8) or the HPT axis for short and is just a way to describe the complex relationship between your hypothalamus, pituitary gland, and thyroid gland.

Here I’ve just renamed it the brain-thyroid connection to simplify its name and make it easier to understand. 

You can do that by following these 4 steps: 

#1. Your goal should be to use the smallest effective dose of thyroid medication possible. 


Thyroid medication will reduce TSH (and the brain-thyroid connection) in a dose-dependent manner. 

The more thyroid medication you take by mouth the more suppressed your brain-thyroid connection will be. 

What’s the solution?

You need to use the smallest effective dose of thyroid medication possible. 

This means you will want to avoid taking any extra thyroid medication if at all possible. 

If your doctor slips up and gives you too much thyroid medication then you risk shutting down the brain-thyroid connection which may result in a drop in the highly effective T3 thyroid hormone. 

You can keep a close eye on this connection by looking at your TSH, free T3, and total T3 levels

These blood tests will help you understand how much T3 is floating around in your system and how suppressed the brain-thyroid connection is. 

It’s worth pointing out here that there are situations in which suppressing the brain-thyroid connection makes sense.

One well-documented situation is the use of thyroid medication after thyroid cancer (9).

TSH suppression dosing in patients with thyroid cancer

Another less common use is suppressing thyroid function temporarily to help with weight loss.

It’s okay to completely suppress the brain-thyroid connection as long as you are replacing both T4 and T3 thyroid hormones with medications.

While levothyroxine only contains T4 thyroid hormone, you can get T3 thyroid hormone from medications like Cytomel and liothyronine.

This allows you to replace the lost T3 levels from suppressive therapies.

#2. Take steps to naturally improve how well your own thyroid gland functions. 

One of the reasons many thyroid patients end up on higher than necessary doses of thyroid medication is that they have problems directly in their thyroid gland. 

These problems ensure that your own thyroid gland is not functioning as well as it can. 

Even though you may have a condition such as Hashimoto’s thyroiditis, which is damaging your thyroid gland, doesn’t mean that you have to just let that damage continue.

hashimoto's disease results in thyroid gland cell death

You can take steps to reduce the autoimmune attack on your thyroid gland which has the potential to restore some thyroid function (this restoration depends on the severity of your disease state).

If you can salvage or naturally improve thyroid function, then you will need less thyroid medication. 

This is why I’m such a big believer in natural thyroid remedies.

Even though they won’t necessarily cure or completely resolve your thyroid problem, even if they have the potential to help you by 5-10% (or more) isn’t that worthwhile?

The only time it may not be worthwhile is if the risks and costs outweigh the potential benefits.

But when we are talking about changes like eating healthier, sleeping better, exercising more, and replacing lost nutrients, it’s clear the cost-to-benefit ratio is very much in your favor.

#3. Provide your thyroid with all the necessary vitamins and nutrients it needs to function optimally. 

Your thyroid gland requires at least 13 different vitamins and nutrients for processes like thyroid hormone production (10), thyroid conversion (11), thyroid cellular sensitivity (12), thyroid conversion in the gut, and thyroid conversion in the liver to occur.

Unfortunately, it’s not uncommon for thyroid patients to have suboptimal levels of many of these important nutrients.

This means your nutrient status may negatively impacting your thyroid function.

the impact that zinc deficiency has on human thyroid function and conversion

It’s my belief that all thyroid patients should ensure that these levels are optimal through lab testing or through supplementation or both.

In the majority of cases, it’s not harmful to take a thyroid-specific multivitamin that contains therapeutic doses of these important pro-thyroid vitamins and minerals.

I’ve spent a lot of time researching and formulating a thyroid multivitamin that takes all of these factors into account.

Even if you don’t want to use my formula, you should still take advantage of my research to see what I’ve included in it and at what doses.

While a thyroid multivitamin is a great starting point, there are plenty of additional supplements that can be used to specifically support and target various pathways necessary for thyroid function.

Some include:

Supplements should never take the place of lifestyle changes, but they can be combined with these therapies for an added boost.

#4. Ensure that other pituitary hormones are functioning well. 

The last thing you will want to ensure is that the other hormones produced by your brain are functioning optimally. 

Your pituitary gland, the same gland that produces TSH, also regulates several other hormones

Your sex hormones (estrogen, progesterone, testosterone), your adrenal hormones (cortisol), and even growth hormone are all regulated by the pituitary gland.

Cortisol, in particular, plays an important role in regulating thyroid function. 

the relationship between cortisol and thyroid function

And if you have problems with the brain-thyroid connection then you can bet you probably also have cortisol or adrenal problems. 

In addition, you might also find that you have problems with your sex hormones which are also being dragged down by your thyroid problem.

Unfortunately, fixing your thyroid doesn’t always resolve your other hormone imbalances which means you will likely need to address both independently.

There are natural and medical treatments available for these hormone imbalances just like there are for your thyroid and which you may need will depend on your situation so the first place to start is usually with testing.

Testing allows you to better figure out where your problem is coming from so that you can then address that problem.

How to Feel Better on Thyroid Medication

Last but not least, you should also take a hard look at what type of thyroid medication you are using. 

Because let’s face it:

Levothyroxine is the most commonly prescribed medication but it just doesn’t work well for most thyroid patients

As I mentioned above, levothyroxine contains only T4 thyroid hormone. 

Other thyroid medications, such as natural desiccated thyroid, contain both T4 thyroid hormone and T3 thyroid hormone and more closely match the ratio that your own thyroid gland produces in a healthy state. 

You should aim to use medications that more closely match the thyroid hormone production of the healthy thyroid gland because that’s how your body was designed to use thyroid hormones.

But don’t take my word for it, we have medical research studies that show that thyroid patients prefer these types of medications (13). 

We also know that people taking these medications often have more energy and experience spontaneous weight loss simply when making the switch. 

You don’t have to switch from levothyroxine to Natural Desiccated Thyroid medications like Armour Thyroid to experience these benefits either.

You can make your own combination T4 and T3 thyroid hormone by adding T3 medication such as Cytomel or liothyronine

In addition, you can also add T2 thyroid hormone in a supplement form to any thyroid medication that you are taking.

Final Thoughts

I want you to know that you don’t have to accept feeling worse on thyroid medication. 

There are things that you can do as a thyroid patient that will not only help you feel better but may help you reverse part or all of your thyroid disease.

This article includes several treatment options that you can take advantage of right away.

Now I want to hear from you:

Are you someone who started thyroid medication but felt worse?

If so, what side effects or problems did you experience when you started?

Were you able to make any changes to fix the problem or are you continuing to suffer now?

Are you planning on making any of the changes listed here or using any of my recommendations?

Leave your questions or comments below! 

#1. ncbi.nlm.nih.gov/books/NBK500006/

#2. ncbi.nlm.nih.gov/pmc/articles/PMC2907600/

#3. ncbi.nlm.nih.gov/pmc/articles/PMC3169862/

#4. ncbi.nlm.nih.gov/pmc/articles/PMC6761896/

#5. pubmed.ncbi.nlm.nih.gov/12915350/

#6. ncbi.nlm.nih.gov/pmc/articles/PMC4699302/

#7. accessdata.fda.gov/drugsatfda_docs/label/2017/021342s023lbl.pdf

#8. pubmed.ncbi.nlm.nih.gov/27347897/

#9. ncbi.nlm.nih.gov/pmc/articles/PMC4737508/

#10. ncbi.nlm.nih.gov/pmc/articles/PMC4049553/

#11. pubmed.ncbi.nlm.nih.gov/8157857/

#12. pubmed.ncbi.nlm.nih.gov/23378454/

#13. pubmed.ncbi.nlm.nih.gov/23539727/

feeling worse on thyroid medication_ Here’s why

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About Dr. Westin Childs

Hey! I'm Westin Childs D.O. (former Osteopathic Physician). I don't practice medicine anymore and instead specialize in helping people like YOU who have thyroid problems, hormone imbalances, and weight loss resistance. I love to write and share what I've learned over the years. I also happen to formulate the best supplements on the market (well, at least in my opinion!) and I'm proud to say that over 80,000+ people have used them over the last 7 years. You can read more about my own personal health journey and why I am so passionate about what I do.

P.S. Here are 4 ways you can get more help right now:

#1. Get my free thyroid downloads, resources, and PDFs here.

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