Hypothyroidism in 21 Lectures

Lecture 14: Thyroid medications

From Hypothyroidism in 21 Lectures by Michael Teplitsky, MD

Author Michael Teplitsky, MD Published July 25, 2026 Read 8 min 1685 words

In the last two lectures we talked about Hashimoto's, the #1 cause of low thyroid in the developed world. We talked about the role of the immune system and the role of the intestine, especially leaky gut syndrome. In the “developed” world we use tons of chemicals, drugs, altered, processed, unnatural foods and the result is great many diseases, including low thyroid.

This lecture will begin the section of hypothyroidism treatment.

First, a person may have hypothyroidism not because there is something wrong with the thyroid gland. The gland may not be functioning properly simply because it is not getting all the things it needs. It’s like a bone marrow, which produces red blood cells, will not make enough of them if there is not enough iron. Nothing is wrong with the bone marrow, but you simply cannot make red cells without iron. Many people have low thyroid because they are low in iodine. In the US the number one cause is Hashimoto’s thyroiditis.

Just like any other organ in the body, thyroid gland needs nutrients, proteins, fats and carbohydrates, it needs vitamins, minerals and anti-oxidants. In short, it needs everything that all the other cells need. But it also has some special needs, for example it needs much more iodine than any other cell. And it needs more tyrosine. It has certain nutritional preferences and it does not like certain foods, and if you disregard that, it can contribute to low thyroid. I will discuss all that in a future lecture,

Today we will be talking about thyroid medications.

With most hormone deficiencies, the treatment is straightforward. If a patient does not have enough of hormone X, he or she will have some symptoms and often some abnormal blood tests. And if hormone X is low then we need to bring it back to normal. For example, many people with diabetes do not make enough insulin because of genetic reasons. So we just give them extra insulin to make the level what it should be. The insulin we use it identical to the insulin produced by the body.

With low thyroid we do the same thing. We check if the thyroid is capable of making the hormones, we make sure that it has all the ingredients. If the gland cannot make enough hormones, like in a case of Hashimoto’s, we give the person extra thyroid hormones to make the levels normal.

Ideally, like with insulin, we should give the same hormones that the body makes, T3 and T4. They do exist and I’ll talk about them in a moment. For now, I’ll just say that they are not very popular because the pharmaceutical industry promotes synthetic hormones because they are more profitable.

You see, natural hormones cannot be patented. To be profitable, a pharmaceutical company wants to have a drug that it can patent. But you cannot patent natural substances. You cannot patent an apple or a carrot. And you cannot patent real T3 or T4. You can only patent something brand new, something that did not exist before you invented it, something not natural.

Sometime in the 1950s someone came up with an idea of a synthetic thyroid, which could be patented. They called it Synthroid, short for synthetic thyroid. They took a real T4 molecule and replaced one hydrogen atom with a sodium atom. T4 naturally has hydrogen, but it does not have sodium. When we substitute sodium for hydrogen we get a brand-new molecule that never existed in nature but it still looks very much like T4 with one minor difference. Now you have something you can patent.

This fake thyroid is not called T4 anymore, it’s called levothyroxine sodium, brand name Synthroid. Even though Synthroid is different from the real T4, it is similar enough that it actually works in about 7-8 people out of 10.

I have heard some people, even doctors, refer to Synthroid as “bio-identical” hormone. Bio-identical means identical in structure and function. For example, we use bio-identical estrogen and progesterone for postmenopausal women. They are exactly the same as the hormones that the body makes. You cannot tell them apart. That’s why they work as if they were naturally produced by the body.

Synthroid is not bio-identical. It is fake. You can easily tell it apart from T4. But structurally it is pretty close, which is why it works in many people.

Ever since it was introduced, Synthroid has been one of the most prescribed drugs in the US, with over 100 million prescriptions a year, which puts it, depending on the year, in the top 5, sometimes in the top 3 prescribed drugs in the country.

Just like fake T4, we can make fake T3, which works in most people. It is sold under the name Cytomel. I told you that about one out of five people taking Synthroid does not have good results. In that case doctors may try adding Cytomel to Synthroid or using just Cytomel.

Ok, so now we know about synthetic thyroid hormones. What many people do not know, including many doctors, is that real natural hormones are available and can be prescribed just like the fake ones.

After all, doctors have been treating hypothyroidism for over 200 years, since early 1800s, long before TSH and other blood tests became available and long before Synthroid was invented. They listened to patient’s symptoms, asked questions, looked for certain signs and made the diagnosis. The emphasis was always on the symptoms. The medication doctors used was something called “desiccated thyroid.” Desiccated means dry.

Desiccated thyroid is not really a drug. It is dried-up thyroid gland of animals, usually pigs. It turns out that all the animals – pigs, sheep, cows, etc. – have a thyroid gland which is exactly the same as human. It produces exactly the same hormones as the human thyroid – T4, T3 and calcitonin. And in exactly the same proportion – about 80% T4 and 20% T3.

If you dry up a thyroid gland of a pig, a sheep or a cow, it eventually turns into a powder from which you can make a pill. Today they mostly use pigs for that. There are many companies that make desiccated thyroid, the most well know is Armour Thyroid, or simply Armour. There are other companies that make dried up thyroid, such as WP thyroid, NP thyroid, Nature-throid, Wellthroid and others. The main ingredient is the same in all of them, the only difference is the binding agent or agents that hold the powder together to form a pill.

The advantage of using Armour is that it provides all the same hormones as the human thyroid gland and in the same proportions. It is a very effective treatment, and many holistic doctors prefer it to Synthroid (synthetic thyroid). Many of my thyroid patients came to me because they were taking Synthroid but did not feel better. But they did great with Armour.

Many medical doctors are reluctant to prescribe Armour. First, many don’t even know that it exists. All they know is Synthroid. Those doctors who do know about Armour have been told that it is unreliable, because who knows how much thyroid you are getting from pigs’ thyroid and so on. This is a lie, because Armour is regulated by the Food and Drug Administration just like all the drugs, just like Synthroid.

And even though Armour is not really a drug, you still need a prescription to get it, so you will have to work with a medical doctor who is willing to prescribe it.

Now, about the dose. Both Synthroid and Armor come in a variety of doses. Synthroid starts at 25 mcg and goes all the way to 300 mcg with many doses in between. Each pill has a different color because a dye is added, so 25 mcg pill is orange, 75 mcg is violet, 100 mcg is yellow and so on. The only one without the dye is 50 mcg, which is white. When I have a patient who is taking Synthroid and is doing well on it, I try to switch her to the 50 mcg white pills. So, if she is taking 75 mcg, which is violet, I give her 1 and ½ of white instead, which gives her the same 75 mcg but without coloring chemicals. Or, if she is taking a 100 mcg yellow pill, I give her 2 whites.

We don’t have this problem with Armor, because all the pills are white, regardless of the dose. The pills range from quarter grain or 15 mg to 5 grain or 300 mg.

Then there is a question of how much medication the patient needs. Most doctors make that decision based on TSH. Just like they decide to treat a person only if her TSH is higher than normal, they are happy when TSH returns down to “normal” Even if the patient still has the symptoms of low thyroid, if her TSH is OK, most doctors will not increase the dose.

Holistic doctors like me listen to the patient, find out if her/his symptoms have improved, and adjust the dose based on how the patient feels. In other words, we do not treat numbers, we treat people.

Now you are familiar with thyroid medications, so in the next few lectures we’ll continue to talk about treatment of hypothyroidism because it’s not enough to just give thyroid hormones. It is important to correct and improve all other factors that contribute to low thyroid.

If you know someone who might be interested in low thyroid, please refer them to LowThyroidDoctor.com so they can download this ebook. Also, if you have questions or comments, please email to DrTeplisky@gmail.com.

As an additional bonus, while available, you can get a free, no obligation 30 min phone consultation with me to see if I can help you figure out if you have low thyroid and what I can do to help you. Just book it online or call my office at 718-769-0997.

FAQ from The Metabolic Journal Editors

These questions are based on this article and related Dr. Teplitsky articles.

What is the main difference between Armour Thyroid and Synthroid?

Synthroid is synthetic T4. Armour Thyroid is a natural desiccated thyroid product that contains T4 and T3. Dr. Teplitsky’s articles explain why that difference may matter for some patients.

How does this lecture fit into the 21-lecture series?

Each lecture builds on the surrounding lessons, so readers can start here and then continue through the full Hypothyroidism in 21 Lectures series.

Should I change thyroid medication on my own?

No. Medication changes should be handled with a clinician. To discuss treatment options with Dr. Teplitsky, call the office at 718-769-0997.

How can I book an appointment with Dr. Teplitsky?

Call Dr. Teplitsky’s office at 718-769-0997 to book an appointment or ask about availability.

Medical Disclaimer: This content is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare provider before making changes to your health regimen.