Why You Are Still Tired on Levothyroxine

What does it mean if you are taking the proper dosage of levothyroxine and you have chronic fatigue? You are still tired. Even though you are taking your levothyroxine thyroid medicine every day without fail, you still have all the original hypothyroid symptoms of fatigue, hair loss, foggy brain, puffy face, weight gain, and elevated cholesterol. Does this mean you need a higher dosage of levothyroxine? Does this mean your levothyoxine is failing you?

Levothyroxine is the mainstream standard of care for thyroid hormone replacement for hypothyroidism, and most people with overt hypothyroidism do “OK” with it. Their symptoms improve and lab testing shows thyroid hormone levels return to the normal range.

However, about 20 percent of people on levothyroxine continue to experience fatigue, brain fog, difficulty concentrating, and other symptoms even after their TSH has normalized within the lab range. Persistent fatigue and and other symptoms of a low thyroid condition can persist even when the TSH lab test is within the normal range.

What is the cause of persistent fatigue on levothyroxine? There are various causes such as:
1) inadequate thyroid hormone levels,
2) the way you take your thyroid medication, and
3) other health conditions such as gastritis or gastric atrophy interfering with absorption, etc. (1-4)

Some people may continue to experience low thyroid symptoms despite having a normalized TSH. Let us review this list in more detail below:

Common Reasons for Fatigue on Levothyroxine

There are multiple explanations for persistent fatigue after starting levothyroxine, including:

Thyroid levels are not yet adequately controlled. Your dosage may need adjustment, particularly after starting treatment or changing the dose.
Medication absorption is reduced. Taking levothyroxine with food or too close to certain supplements and medications can interfere with absorption.
Another condition may be causing the fatigue. Iron deficiency, sleep problems (insomnia), depression, nutritional deficiencies, and other health conditions can cause symptoms that mimic hypothyroidism.
Symptoms persist despite normal thyroid levels. Some people continue to experience fatigue or brain fog even when TSH and other thyroid levels have normalized within the lab range after treatment with levothyroxine. Additional testing is needed.
It is not a thyroid disorder. Symptoms could be due to other causes. Fatigue is common and can have many causes, so thyroid disease shouldn’t automatically be assumed.

This is why persistent fatigue while on levothyroxine requires a complete medical evaluation, rather than assuming inadequate dosage which needs to be increased.

Why You Might Still Feel Tired on Levothyroxine With a Normal TSH

Why is this happening? Is the thyroid medication inadequate? Unexplained symptoms such as fatigue, brain fog, weight changes, and low mood could persist even after treatment with thyroid medication. In fact, in 2016, Antonio Bianco, M.D. reported some patients have persistent hypothyroid symptoms even when the TSH is within the normal range, which is why evaluation of a thyroid disorder requires a more complete thyroid panel. (5)

Your healthcare provider, primary care or endocrinologist will typically order a test called the TSH with reflex to Free T4. What this means is the lab will run the Free T4 test only if the TSH is outside of the lab range for normal. If the TSH is normal they will not run the Free T4 test. For completeness, our TruemedMD clinic in Davie, Florida will always do a complete thyroid lab panel which includes: TSH, Free T3, Free T4 reverse T3, thyroid antibodies, anti-gliadin antibodies, H. Pylori breast test and serum selenium. (1-4)

A normal TSH is a useful test for monitoring hypothyroidism, but remember, the TSH test may be unreliable and may not fully explain the patient’s symptoms or how they are feeling. Automatically increasing the thyroid hormone dosage may not be effective when the medication is levothyroxine. We will explain why below.

Best Practices for How to Take Levothyroxine

How you take the levothyroxine tablet can affect absorption, i.e. how much medication your body actually absorbs. For good absorption, Mayo Clinic recommends taking levothyroxine with a glass of water first thing in the morning on an empty stomach, 30 to 60 minutes before breakfast. (6-7)

Keep these points in mind:

Take your levothyroxine tablet as prescribed.
Take you tablet with water half hour before breakfast, not with breakfast or other beverages.
Avoid taking calcium supplements or iron supplements at the same time as the levothyoxine.
Tell your healthcare provider about antacids, cholesterol-lowering medications, supplements, and other medicines you may be taking.
Do change your dosage on your own. Always discuss first with your health care provider.

Calcium and iron can interfere with thyroid hormone absorption, and Mayo Clinic recommends separating these products from thyroid medication by at least four hours.

Thyroid Tests When You Still Feel Fatigue and Tired?

Thyroid testing can help determine whether your treatment is adequate for your hypothyroid condition. As mentioned above, mainstream medicine will use the TSH with reflex to Free T4 to monitor levothyroxine therapy.

In this situation, a complete thyroid panel is required for a complete medical evaluation. At TruemedMD, we do a complete thyroid panel consisting of TSH, free T3, free T4, reverse T3, thyroid antibodies, H. Pylori breast test, antigliadin antibodies, serum selenium, iron and ferritin. Thyroid antibody testing is useful for diagnosis of autoimmune thyroid conditions such as Hashimoto’s thyroiditis. H. Pylori Breath test is useful since H. Pylori infection of the stomach can impair levothyoxine absorption. Other thyroid tests may be appropriate depending on your diagnosis and symptoms. (1-4)

The key point is that your laboratory results should NOT be interpreted in a vacuum. They should be interpreted as part of a larger evaluation which includes medical history, review of symptoms, current medications, physical finding, and previous laboratory test results.

What If Levothyroxine Is Not Relieving Your Symptoms?

If your thyroid levels are in the expected range but fatigue continues, the next step is not necessarily a higher dosage of levothyroxine. Too much thyroid hormone dosage can cause thyroid excess symptoms of tremor, shakiness, sleep difficulties (insomnia), loose stools, and heart palpitations (tachycardia).

For patients with persistent symptoms on levothyroxine, many will respond better to combination treatment using T4 and T3. Combination therapy has been studied in patients on levothyroxine with persistent symptoms, showing this subgroup feels better on combination therapy with both T3 and T4 contained in natural desiccated thyroid (NDT). Another form of combination therapy is to add a small dosage of T3 (cytomel) to the levothyoxine.

When Should You Talk to Your Doctor About Persistent Fatigue?

Talk with your healthcare provider if fatigue continues after starting levothyroxine, especially if you have persistent hypothyroid symptoms, fatigue, cold intolerance, constipation, weight gain, hair loss, or difficulty concentrating (foggy brain).

Bring your current medication dose, the way you take it, other medications or supplements you use, and recent thyroid test results to your appointment. This information can help your provider determine whether your thyroid treatment needs adjustment or whether another cause of fatigue, or a different thyroid doctor, should be considered.

Do not increase, decrease, or stop levothyroxine without medical guidance.

Still Tired Despite Taking Levothyroxine?

If fatigue continues despite thyroid treatment, then we can help. At our TruemedMD clinic in Davie, Florida, our medical director Jeffrey Dach MD, approaches thyroid treatment by reviewing the full clinical picture, including medical history, review of symptoms, physical findings, laboratory findings, and your response to treatment, to determine if you are a good candidate for switching from levothyoxine to natural desiccated thyroid (NDT).

Frequently Asked Questions

Why am I still tired of levothyroxine?

You may remain tired because your thyroid levels are not yet adequately controlled, the medication is not being absorbed consistently, or a different condition is causing the fatigue. Some people continue to experience symptoms despite normal TSH levels.

Can you still have hypothyroidism symptoms with a normal TSH?

Yes, some people report persistent symptoms such as fatigue or brain fog after TSH has normalized on treatment with levothyroxine. However, these symptoms are not specific to hypothyroidism, so other causes should be considered.

How should I take levothyroxine for better absorption?

Levothyroxine is generally taken on an empty stomach with water. Calcium and iron supplements, certain medications, and some foods can interfere with absorption, so discuss your medication routine with your healthcare provider.

Should I increase my levothyroxine if I am still tired?

No. Persistent fatigue does not automatically mean you need a higher dose. Your healthcare provider should review your thyroid tests, symptoms, medication routine, and other possible causes before changing your levothyroxine dosage.

Conclusion:

About 20 percent of patients on levothyroxine have persistent symptoms of a hypothyroid condition with fatigue, brain fog, weight gain, constipation, hair loss, puffy face, cold intolerance, depression, etc. These patients feel much better switching to combination therapy with T3 and T4, such as natural desiccated thyroid (NDT). If fatigue continues despite levothyroxine thyroid treatment, we can help. Contact our office at the TruemedMD clinic in Davie, Florida, our medical director Jeffrey Dach MD, will review the full clinical picture, including medical history, review of symptoms, physical findings, laboratory findings, and your response to treatment, to determine if you are a good candidate for switching from levothyoxine to natural desiccated thyroid (NDT).

Articles with Related Interest:

Antonio Bianco: TSH Inadequate for Thyroid Dosing

Chronic Fatigue, The Non-Mystery

Combination T3 and T4 Reduces Mortality and Dementia

Natural Thyroid is Better, Part One

Natural Thyroid is Better Part Two

Natural Thyroid is Better Part Three

Paradigm Shift from Levothyroxine to Combination T3 T4

The Unreliable TSH Test

Which Thyroid is Best, Natural Synthetic or Combination?

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