Conventional medicine believes that if you have an underactive, chemically ablated or surgically-removed thyroid gland, that all you need is levothyroxine - the synthetic form of the T4 hormone. Levothyroxine is also known by its brand names: Synthroid, Levoxyl, Eltroxin, Tirosint, and Levothroid, among others.
T4 is the inactive thyroid hormone, and must be converted into the active thyroid hormone T3 - triiodothyronine — in order to deliver oxygen and energy to cells, and resolve hypothyroidism. The conventional belief is that the levothyroxine will adequately and effectively convert in the body to T3.
As a result, millions of people who are diagnosed with hypothyroidism, or who are hypothyroid after thyroid surgery or Radioactive Iodine (RAI) treatment, are given a prescription for generic or brand name levothyroxine, and sent on their way.
Even with levothyroxine treatment, however, many of these patients, and you may be among them, continue to experience hypothyroidism symptoms, such as weight gain, fatigue, depression, brain fog, aches and pains, infertility, hair loss, low sex drive, and other signs of an underactive thyroid.
The reason? They are still hypothyroid — and don't have enough T3 available to actually resolve the hypothyroidism symptoms.
Why Isn't Levothyroxine Working for You?
Cutting-edge hormonal medicine practitioners are far ahead of conventional medicine in understanding a key fact: you may have genetic, nutritional or hormonal factors that prevent you from converting T4 to T3 effectively, leaving you with insufficient T3. Conventional medicine does not acknowledge the concept of ineffective conversion, or the role of T3 in hypothyroidism treatment. But again, T3 is the active hormone at the cellular level, so if you are unable to convert T4 to T3 effectively, and do not have optimal levels — or you have high levels of the inactive blocking hormone Reverse T3 — you will be hypothyroid, even if your Thyroid Stimulating Hormone (TSH) blood test shows you to be within the reference range.
What Steps Should You Take?
- First, understand that the TSH test and levothyroxine are only one component of thorough hypothyroidism diagnosis and care.
- Next, your doctor should be testing for Free T3 - and Reverse T3 (an inactive form of T3) - to determine if you are receiving optimal treatment.
- Reverse T3 should be low, and Free T3 should fall in the top half, or even the top 25th percentile — of the reference range, in order for you to be receiving optimal hypothyroidism treatment.
- Understand that if your Free T3 is not optimized, or if elevated Reverse T3 is present — or both — you very likely may benefit from the addition of a T3 medication to your levothyroxine treatment.
- Know that T3 can be prescribed in the form of the brand name drug Cytomel - a synthetic T3 - or the generic for Cytomel, known as liothyronine.
- You may be one of the people who respond better to a sustained-release/time-release compounded form of T3, available by prescription from compounding pharmacies.
- You may not feel your best on levothyroxine plus T3, but rather with the prescription natural T4/T3 combination drug called natural desiccated thyroid (NDT), also known by the brand names Nature-throid and Armour Thyroid.
- Finally, you may actually do best on a T3-only therapy. This can be helpful if you have very high Reverse T3, or who have underlying adrenal dysfunctions.
The Bottom Line?
If you are on levothyoxine-only treatment for your hypothyroidism, and still have symptoms, have your Free T3 and Reverse T3 tested, and seek T3 treatment if these levels are not optimal. Hypothyroidism treatment can be complicated, and the better you understand how it works, the further along you will be in feeling well.