There’s a lot of confusion about the role of thyroid hormone replacement medication in the treatment of hypothyroidism and Hashimoto’s disease. Common questions about hypothyroidism medication include:
I still have symptoms of hypothyroidism despite taking Synthroid (Levothyroxine). What’s going on?
Is combination T4/T3 therapy better than Synthroid?
Is natural hormone medication better than synthetic hormone replacement?
Is it possible to get off thyroid medication with natural health interventions?
It’s very important to understand that thyroid medication alone may not be enough to resolve symptoms associated with hypothyroidism. Thyroid medication should be part of an overall treatment plan, but it’s critical to also address other contributing factors. For many thyroid patients, this means taking steps to normalize gut imbalances, reduce inflammation, and heal leaky gut. As we often see, gut health can be the missing puzzle piece that finally resolves years of frustrating symptoms.
In this article, we’ll answer your questions about thyroid medication and give you the information you need to live a healthy, symptom-free life.
3 Steps to Getting Thyroid Treatment Right
At a very high level, treating autoimmune thyroid disease and hypothyroidism involves a three-step approach:
1. Take standard thyroid medication to bring thyroid hormone levels up to a normal range.
2. Use gut-healing therapies to resolve symptoms.
3. Retest thyroid hormone levels and adjust medications as needed.
This three-step approach is similar to how you would manage a slow tire leak. Lab testing is like using a tire pressure gauge to check air levels. Taking thyroid medications is like refilling the tire daily to keep your tire serviceable.
But ultimately, there’s a bigger problem that needs to be resolved. For your tire, it means going to a tire shop and having the puncture fixed. For your health, it means healing your gut. Once fixed, you should recheck tire pressure (or retest thyroid levels) to see if air/medications are still required.
How Not to Treat Hypothyroidism
We see a lot of thyroid patients at the Austin Center for Functional Medicine who have been struggling for years with thyroid symptoms even after consulting multiple healthcare providers. Medical advice for thyroid patients is usually well-intentioned but frequently falls short due to these common errors:
Treating lab values and not the person: If you take thyroid medication and your lab tests are normal, many conventional doctors and endocrinologists consider your problem solved. They may prescribe antidepressants for persistent symptoms like fatigue and brain fog.
Ignoring the gut-thyroid connection: An overarching issue is that the majority of practitioners still don’t recognize the critical, well-researched connection between gut health and thyroid health.
Just like refilling your tire with air won’t solve a tire puncture, popping a hormone replacement pill will not resolve your thyroid condition if poor gut health is the real reason for symptoms, autoimmunity, and low thyroid function.
Let’s take a brief look at how gut health affects thyroid health. Then, we’ll answer your hypothyroidism medication questions.
The Gut-Thyroid Connection
Gut conditions and thyroid conditions are very often found in the same patients. This can be true even if you don’t have obvious gut symptoms.
This type of research only suggests a possible gut-thyroid relationship but does not prove that gut problems cause thyroid issues. For stronger evidence, we look to clinical trials that investigate whether gut treatments can resolve thyroid conditions. Here, we see impressive results:
Is Combination T4/T3 Therapy Better Than T4 Medication?
Combination T4/T3 therapy is popular in alternative health circles. However, we’ve done a deep dive into the research and determined that, for most people, combination therapy is not more effective than T4 medication and may actually be detrimental to patients’ health.
If you want a quick review of how T4 and T3 thyroid hormones work, here’s a summary:
T4 and T3 Hormones
T4 and T3 hormones regulate body functions such as heart rate, energy production, body temperature, weight, growth of hair, skin, and nails, and more.
T4 (thyroxine): This is a thyroid hormone that contains four iodine atoms.
T3 (triiodothyronine): This thyroid hormone contains three iodine atoms.
T4 is produced in your thyroid gland along with a small amount of T3. Most of the T3 that your body uses must be converted from T4. This conversion process involves removing one of the iodine atoms and mostly takes place in the liver and kidneys.
Proponents of T4/T3 hormone replacement therapy suggest that poor T4 to T3 conversion is the reason why standard T4 therapy fails to resolve symptoms.
We recently reviewed the evidence for using combination therapy and published results in our Future of Functional Medicine Clinical Newsletter. Our review included 16 randomized clinical trials and one meta-analysis. We did not find significant evidence that combination T4/T3 therapy, at any dose, was more beneficial than standard T4 medication.
The Real Reason Your T3 Is Low
Low T3 is a condition associated with poor nutrition, inflammation, and chronic illness . Rather than prescribing hormone replacement for low T3 levels, treating gut imbalances and nutritional deficiencies will likely provide greater benefits for patients.
Overprescribing T3 Can Be Harmful
Indiscriminately prescribing combination therapy to thyroid patients with unresolved symptoms is a potentially harmful practice. Excess T3 does have side effects.
As we have often seen in the clinic, taking T3 when it’s not needed can increase fatigue, worsen mood, and impair sleep. Some patients suffer with this for years before we figure this out.
Practice guidelines for the European Thyroid Association recommend caution in prescribing combination T4/T3 therapy . Guidelines published by the American Thyroid Association and the American Association of Clinical Endocrinologists do not recommend combination T4/T3 therapy .
Natural Thyroid Hormone Medication vs. Synthetic Hormone Replacement
Natural is always better, right? While I generally agree, thyroid medication may be one example where this rule of thumb does not apply.
Unlike levothyroxine, which is produced in labs, desiccated thyroid hormone is derived from the thyroid glands of pigs. It is a combination T4/T3 medication. The ratio of T4/T3 is fixed and cannot be adjusted in the same way as synthetic thyroid medication. Desiccated thyroid hormone is sold under brand names such as Armour Thyroid, Nature-Throid, and WP Thyroid.
Some patients seem to prefer natural thyroid medication, as was found in one study that compared patients taking levothyroxine and dessicated thyroid hormone . However, in this study, researchers found no significant differences in symptoms between the two therapy groups.
Rather than searching for the “perfect” thyroid medication, we recommend that patients take a standard T4 medication and turn their attention to improving underlying gut imbalances.
Can You Get off Thyroid Medication With Gut Health Interventions?
Thyroid patients are usually told that they must continue thyroid hormone replacement therapy for life. However, if gut therapies can improve thyroid health, is it possible to get off thyroid medication?
There are two scenarios that can result in changes to thyroid medication dosage:
Sometimes, better absorption may mean that you’re getting too much thyroid hormone. If you’re taking hypothyroidism medication and healing your gut, you may start to notice hyperthyroidism symptoms, such as:
Feeling jittery and restless
Racing heart rate
It’s important to retest your thyroid hormone levels and adjust medication dosage as your gut heals.
Thyroid Medication Is Overprescribed
There’s another surprising reason why some patients are able to discontinue thyroid medication. Research suggests that thyroid medication is overprescribed, which means that many thyroid patients are over medicated.
One study shows that up to 60% of patients taking thyroid hormone replacement may be doing so unnecessarily [54 Trusted SourcePubMedGo to source]. In this study, patients who had been taking Synthroid for a number of years paused their medication for 6-8 weeks. After several weeks, 60.8% of patients had normal levels of thyroid hormone, meaning they did not require thyroid medication.
This research is confirmed by our clinical experience. We frequently see patients who have been misdiagnosed and prescribed thyroid medication despite having thyroid lab test results in the normal reference range.
Patients with Grave’s disease can benefit from a similar, gut-focused treatment approach to improve their thyroid health. Treating underlying gut disturbances that drive autoimmunity can help patients avoid extreme thyroid treatments, such as radioactive iodine, that leave the thyroid gland permanently damaged.
Gut Treatments for Thyroid Health
If you’re taking thyroid medication, your TSH and T4 levels are normal, and you’re still experiencing symptoms, the gut-healing steps described in my book, Healthy Gut, Healthy You, can be the key to improving your health.
There are three important approaches to beginning to improve gut health:
Follow an anti-inflammatory diet, such as the paleo diet.
As your gut heals, blood tests can help you monitor your progress and identify any need for thyroid dose adjustments. While some healthcare practitioners suggest complex methods for monitoring thyroid hormone levels, we advise a simpler approach:
TSH (thyroid-stimulating hormone) levels are the most important indicator for assessing hypothyroidism and hyperthyroidism. TSH testing is a cheap and effective measure for monitoring and adjusting thyroid hormone dosage.
T4 testing should be included to determine if you have central hypothyroidism, a rare disorder caused by pituitary gland dysfunction.
TPO is a thyroid antibody that indicates you have autoimmune thyroid disease. While there are other thyroid antibodies that can be measured, TPO levels are considered the most reliable marker for Hashimoto’s thyroiditis.
As your gut heals, TPO levels should reduce and TSH and T4 levels may improve. However, it’s never a good idea to be completely focused on the lab test numbers. What matters most is how you feel. At our clinic, TPO levels below 500 are considered a win for autoimmune thyroid patients [56 Trusted SourcePubMedGo to source]. There’s simply no need to stress over getting thyroid antibody levels down to zero.
Hypothyroidism Medication Is Only Part of the Solution
Hypothyroidism medication helps to normalize your thyroid hormone levels, which is important for regulating body functions. But thyroid medication isn’t always effective for eliminating symptoms such as fatigue, brain fog, poor mood, and constipation.
That’s because thyroid disorders aren’t just simple problems of high or low levels of thyroid hormones. Thyroid problems and persistent symptoms are typically signs of underlying issues, including gut dysbiosis, gut inflammation, and leaky gut.
Thyroid medication is an important part of an overall strategy that should also include restoring good gut health.
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