What Is the Best Thyroid Medication?

Man comparing medications
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I am often asked a question by fellow thyroid patients: "What is the best thyroid drug to treat hypothyroidism?" Let's take a look at why there isn't an easy, cut-and-dry answer.

Thyroid Medication Options

First, and most importantly, you need to know there are options. Many thyroid patients who require thyroid hormone replacement to treat their hypothyroidism do not realize or are never told that there is more than one medication.

You can read a more detailed article about thyroid hormone replacement, but here's a quick overview:

Levothyroxine - a synthetic form of the T4 hormone - is the drug by the mainstream and conventional medical world. Commonly-known brands include Synthroid, Levoxyl, and Tirosint, and various generics from different manufacturers are also available. Many thyroid patients are only told about and offered levothyroxine, and many conventional physicians will prescribe only this drug for their hypothyroid patients.

Liothyronine - a synthetic form of the T3 hormone - is far less commonly prescribed by endocrinologists, but is more commonly used by integrative physicians and physicians with expertise in hormone balance. The brand name in the U.S. is Cytomel, and a generic is also available. Many thyroid patients are never tested for Free T3 -- to determine if they are low in T3, the active thyroid hormone, except by hormone balance experts and integrative and/or naturopathic physicians.

Natural Desiccated Thyroid - also known as NDT, "natural thyroid," "porcine thyroid" (or derogatorily by some physicians as "pig thyroid" -- is a prescription drug derived from the dried thyroid glands of pigs. Common brands are Armour Thyroid and Nature-throid, and a generic is also available. Most endocrinologists, and many mainstream physicians do not support or prescribe use of natural desiccated thyroid drugs.

What Does the Research Say?

Interestingly, the research doesn't offer a definitive answer. Some studies say that there are no proven benefits to the addition of T3 to levothyroxine therapy. Other studies, like the major Danish study published in the European Journal of Endocrinology, found that T4+T3 combination therapy was superior to T4/levothyroxine only treatment. A recent study found that natural desiccated thyroid drugs were a safe and effective alternative to levothyroxine.

Bottom line? Until someone does a huge, flawless, double-blind, crossover, peer-reviewed study looking at safety, effectiveness, and symptom relief of levothyroxine, levothyroxine plus liothyronine, and natural desiccated thyroid -- and publishes the results in a major medical journal -- we won't have a definitive answer from the scientific point of view.

Patients, Physicians Have Varying Preferences 

As you can tell, the answer to the question of "what is the best thyroid drug" will vary wildly, depending on who you are asking.

If you are asking me, as a patient advocate, my answer is always the same. The best thyroid drug to treat hypothyroidism is the one that safely and best resolves the symptoms of each individual patient.

In other words, one size does not fit all, and a drug that works perfectly for one patient may not for another.

If you ask conventional endocrinologists, or read their official "guidelines" (often funded, not surprisingly, by drug companies) they almost universally recommend only levothyroxine - synthetic T4 -- to the exclusion of other options. Some of them even go so far as to tout one particular brand. (Again, not surprising, as some of them receive grants, awards, and other financial support from the drug's maker.)

If you ask holistic practitioners, a small subset feel strongly about only natural desiccated thyroid drugs -- to the exclusion of synthetic drugs.

But I take my cues from patients and from many open-minded and cutting-edge integrative practitioners who are successfully caring for thyroid patients. Find the thyroid drug that safely works best for you, and there's your answer: that's the best thyroid drug -- for YOU.

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