iThei mdcdaelcinfd o c elllllrlllll ftecdf hslcinfd olidfmdhtlbtktbeWhich Thyroid Medication Is Best?
Thyroid hormones are known to have a very narrow therapeutic index.
They are “Goldilocks” medications, in that they have to be dosed just
right to ensure effectiveness and prevent adverse drug events. Thyroid
hormones are dosed in micrograms—that is just 1/1000th of a milligram!
When the dose is a teensy bit too high, we may experience symptoms of
hyperthyroidism, and when the dose is a teensy bit too low, we can have
symptoms of hypothyroidism!
Conventional physicians will usually prescribe Synthroid® or levothyrox-
ine, a synthetic version of T4. Natural desiccated thyroid (NDT) medi-
cations, which may include Armour®, Nature-Throid®, WP Thyroid® and
other animal organ derived products, are not usually recommended by
conventional physicians because of past issues with quality control.
In the past, Armour® has had some discrepancies in the dosages between-
batches, but this does not seem to be the case at present due to improved
quality control. Nature-Throid®, another desiccated thyroid medication,
has never been recalled for inconsistent T4 and T3 hormones.
Conventional treatment guidelines indicate there is no benefit from tak-
ing combination T3/T4 products and T4 products are superior. Most
of these claims, however, are based on studies funded by pharmaceutical
companies with a potential conflict of interest in promoting the use of
their own products.^10
Understanding thyroid physiology, I believe combination products may
be advantageous for many patients with Hashimoto’s. Some Hashimoto’s
patients are unable to properly and efficiently convert T4 to T3. For ex-
ample, zinc is required to convert T4 to T3, and as you will come to learn
in the Depletions & Digestion chapter, Hashimoto’s patients are often
zinc-deficient.
Under stressful situations, T4 gets converted to reverse T3 instead of T3.
Reverse T3 is an inactive molecule related to T3 but without any physi-
ological activity—it is a dud that just takes up space! In cases where a lot
of reverse T3 is produced, adding a combination product that contains
T3 helps ensure that the right hormone is getting to the right receptors.
Additionally, many patients report they feel better taking a combination
T4/T3 product.