6 Reasons Your Thyroid Medication Might Not Be Working

As many as 20 million Americans have some form of a thyroid problem.

Hypothyroidism, or low thyroid function, is the most common. And because every cell of your body depends on the thyroid hormone, hypothyroidism can lead to many health problems, including weight gain, fatigue, and digestive issues.

In certain cases, it's more severe: Some research shows a link to depression, and one study found that people with underlying low thyroid problems were twice as likely to have heart attacks.

In terms of treatment, patients with hypothyroidism are typically given a thyroid replacement hormone as medication and care stops there. Because of this, some people still experience low thyroid symptoms despite medication and "normal" labs. That's why I often have people ask me:

I'm on a thyroid medication but it isn't working for me. Why?

If you're still having low thyroid symptoms despite medication, it's probably not that "you're just depressed" or "getting older." Here are some other factors you should consider:

1. Fillers

Thyroid drugs are pretty comparable as far as their active ingredients, with the biggest variable being the inactive ingredients. Because everyone is different, and many thyroid problems are autoimmune in nature, the fillers used are what you may be having a negative response against. Drug formulas can change, so it's important to check your individual medication. And if you think you might be having a reaction, immunological labs can uncover certain intolerances you may be having.

2. "Normal" lab ranges

On your lab you'll see a "Reference Range." This range is what's considered normal in mainstream medicine. That range is based on a bell curve, a statistical average of the population of that particular lab you went to. People who go to labs are typically sick people. So if your result comes back within that reference range, it doesn't automatically mean it's at the optimal level for you.

In addition to the interpretation of the basic thyroid labs your doctor runs, running more expansive thyroid testing can also be helpful in uncovering these issues. To get a full list of thyroid labs and their optimal ranges, check out Why Your Lab Results Could Be Lying About Your Thyroid Health.

3. Underlying thyroid dysfunctions

Sometimes there are other thyroid problems that won't be solved by a pill alone. Thyroid conversion problems and Hashimoto's disease (autoimmune thyroiditis) are two often overlooked underlying thyroid issues that should be ruled out.

4. Inflammation

Inflammation can significantly inhibit thyroid hormone function. Addressing this means dealing with the underlying causes of inflammation, including a poor diet, stress, and toxins. Thyroid resistance, similar to insulin resistance, is one reason why your thyroid medication may not be working for you. I recommend working with a qualified functional medicine practitioner to uncover and address chronic inflammation.

5. Decreased absorption

There are several medications that alter the absorption or activity of T4, a hormone produced by the thyroid. These might include commonly prescribed drugs like antacids, antibiotics and antifungals, antiarrhythmia medications, cholesterol-lowering medications, diabetic medications, diuretics, hormone replacements, and pain medications.

Some foods may decrease the absorption of thyroid hormones such as soy-based and high-fiber foods. Iron and calcium supplements can also inhibit thyroid hormone function.

According to the drug manufacturers, it’s best to take your medications four hours before or after you ingest foods, drugs, or supplements that can affect its effectiveness.

6. Non-thyroid factors

There are other underlying health problems that can both mimic low-thyroid symptoms and also complicate thyroid function. Candida overgrowth, leaky gut syndrome, adrenal fatigue, and other metabolic problems should all be investigated.

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