Armour Thyroid and Travel: Storage, Timing, and Time-Zone Strategies

What the Armour Thyroid label says about taking it

Armour Thyroid is dosed in milligrams of dried thyroid, supplied from 15 mg (1/4 grain) to 300 mg (5 grain), and each grain carries 38 mcg of levothyroxine (T4) and 9 mcg of liothyronine (T3) [1]. The label's pharmacology section says fasting increases absorption of levothyroxine and that the hormones in desiccated thyroid extract preparations are absorbed in a manner similar to the synthetic hormones [1]. It gives no food or timing instructions for the tablet [1].

What is documented about the tablets

FDA states that animal-derived thyroid medications are not FDA approved, and the Armour Thyroid label says the product has not been approved by FDA as a new drug [2][1]. FDA says these tablets have not been reviewed to ensure safety, purity and potency, and that tablets made from the same manufacturing batches may not always provide the same thyroid hormone levels [2].

FDA also says unapproved animal-derived thyroid medications are not eligible for compounding because they are regulated as biological products under the Public Health Service Act [2].

Dose changes and symptoms on the road

The label says dose readjustment should be made within the first four weeks of therapy, after clinical and laboratory evaluation including serum T4 and TSH [1].

The relative T3 excess in desiccated thyroid can produce serum T3 levels above normal that peak shortly after a dose [6]. The label describes an excessive dose as causing a hypermetabolic state, and lists chest pain, rapid pulse, palpitations, sweating, heat intolerance and nervousness as symptoms to report [1].

Thyroid labs after a trip

Biotin and biotin-containing supplements can cause erroneous TSH, T4, and T3 immunoassay results; the Armour Thyroid label advises stopping biotin supplementation at least 2 days before thyroid testing [1].