FDA To Tighten Regulation of Natural Thyroid Medications
The FDA announced it is looking at taking action against companies selling “unapproved” animal-based thyroid drugs, but not right away. Additionally, FDA Commissioner Martin Makary stated that he hopes to approve a biological thyroid drug. Right now, none of the natural thyroid medications being marketed are approved as drugs by the FDA, although they are available from compounding pharmacies. The FDA says that “these unapproved animal-derived thyroid medications are not eligible for compounding because these products are regulated as biological products under the Public Health Service Act.”
In the meantime, many patients are concerned they will lose access to a medication that works for them for their low thyroid (hypothyroidism) symptoms. The FDA says that the concentrations in the natural products are not consistent and the source materials (dried or “desiccated” thyroid gland, usually from a pig) may have impurities. Examples of these products include Armour Thyroid, NP Thyroid, Nature Thyroid, and more.
FDA Press Release (August 2025): FDA Actions Address Unapproved Thyroid Medications
Medscape: FDA Warns of Future Action on Animal-Derived Thyroid Drugs
On our website, on average, many patients with low thyroid or Hashimoto’s disease are satisfied with products like Armour Thyroid, the natural (porcine) version of thyroid hormone. They find it works better than synthetic versions like levothyroxine or liothyronine sodium. Check out patient testimonials for Armour Thyroid.
In a related item about thyroid meds, more than 150,000 bottles of Accord’s generic levothyroxine tablets are under recall because of potency problems (subpotent: they have less than the labeled concentration of medication):
August 2025 Recalls Levothyroxine by Accord
Some Substack newsletters focused on the topic of low-thyroid conditions and treatments that are covering the FDA news and worth checking out include:
Note that The Thyroid Clinic (below) is U.K.-focused but the stories and news may be of interest to all:
