The FDA has announced its intention to ban natural desiccated thyroid medicines used safely by millions of hypothyroid patients, leaving them with only a synthetic version that is much less effective. Action Alert!
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THE TOPLINE
- The FDA has stated it plans to remove all natural desiccated thyroid (NDT) products from the market within 12 months, impacting millions who rely on NDT for effective thyroid hormone replacement.
- Despite decades of safe use and minimal adverse event reports, the FDA demands costly approval processes that NDT manufacturers cannot realistically meet.
- This enforcement is part of a broader and long-term pattern of restricting access to natural and compounded medicines, limiting patient choice, and consolidating pharmaceutical industry control.
In a devastating blow to health freedom, the FDA has announced it wants to eliminate access to all forms of natural desiccated thyroid (NDT) medicine—including compounded and commercial products such as Armour Thyroid. In an August 6, 2025 letter to manufacturers, importers, and distributors, the agency declared these long-used medicines to be “unapproved biologics” and warned that they will be subject to enforcement. The FDA has said it will allow only 12 months of “enforcement discretion” before the ban takes effect, presumably to give patients time to “transition” to FDA-approved synthetic thyroid drugs.
This will remove a critical option for millions of patients with hypothyroidism, a condition in which the thyroid does not produce enough hormone to sustain healthy bodily functions. An estimated 30 million Americans have hypothyroidism, and 10–29% of them rely on NDT as their primary hormone replacement therapy. That’s as many as 8 million people.
Why NDT Matters
NDT is made from dried, ground pig thyroid glands and contains the full spectrum of thyroid hormones—T1, T2, T3, T4, and calcitonin—closely mirroring what the human thyroid produces. Synthetic, FDA-approved alternatives contain only one hormone (either T4 or T3). For many patients, particularly those who cannot efficiently convert T4 into T3, synthetic drugs simply don’t work. Switching these patients to a T4-only drug can mean a return of debilitating symptoms: extreme fatigue, depression, weight gain, brain fog, and more.
Compounded NDT is even more essential for those who need customized dosages or delivery systems to match their unique hormonal needs—something mass-produced drugs cannot do. When thyroid glands are not functioning properly, they rarely stop producing hormones completely—they are producing the wrong levels of hormones. Doctors must determine how to correct these imbalances based on observed hormone levels in each patient. Additionally, hormone levels can fluctuate. This is why the one-size-fits-all FDA-approved options are not sufficient for many patients.
The FDA’s Thin Justification
The FDA claims NDT has not been reviewed for safety and efficacy and warns about risks such as inconsistent potency and viral contamination. But the agency’s own data shows just 500 adverse events reported between 1968 and 2025—about nine cases a year. This is hardly evidence of a public health threat that warrants eliminating an option millions of patients rely on.
The real obstacle is not safety—it’s the agency’s demand that NDT go through the Biologics License Application (BLA) process. NDT products were, for most of this century, grandfathered in as pre-1938 drugs (that is, drugs in use before the passage of the Food, Drug & Cosmetic Act of 1938), but a 2010 law passed by Congress changed the definition of a “biologic” to include proteins, which, according to the FDA, puts NDT and other thyroid hormone drugs into the biologics category.
Like the new drug approval process, the BLA process is not appropriate for NDT. NDT is a complex, naturally derived substance, not a single synthetic molecule, making it difficult and extremely expensive to navigate the BLA pathway. That’s one reason no company has sought approval, and why this enforcement action is effectively a permanent ban.
Clinical trials are even more infeasible for compounded drug products. Clinical trials cannot be conducted on compounded medicines given the highly varied and individualized doses and delivery mechanisms used. This is the whole point behind compounded medicine: to customize medicines to meet individual patients’ needs.
You may be wondering: why is this happening under the leadership of RFK Jr. and Dr. Marty Makary? First, NDT has been in the FDA’s crosshairs for years—this crackdown was already set in motion long before they took office. Second, the legal issues are complicated: because NDT is now classified as a “biologic” rather than a drug, changing its regulatory pathway would require an act of Congress, not a decision by the administration alone.
Part of a Bigger Pattern
This is not an isolated incident. The FDA has been systematically eliminating access to natural medicines that fall outside the pharmaceutical industry’s model. Bioidentical hormones, compounded peptides, and homeopathic medicines are all under attack, with the same “lack of FDA approval” rationale, regardless of their track records of safety and patient benefit.
By insisting that FDA approval is the only legitimate standard for access, the agency is acting less like a protector of public health and more like a gatekeeper for Big Pharma, consolidating the market into a handful of high-cost, patent-protected products while stripping patients and practitioners of treatment choices.
What’s at Stake and Call to Action
If this ban goes forward, countless patients will be forced onto drugs that do not work for them, with real consequences for their health, livelihoods, and quality of life. The FDA is effectively telling these patients: Your experience doesn’t matter. Your doctor’s judgment doesn’t matter. Only our approval does.
We must act now to stop this ban and preserve access to NDT. ANH-USA is mobilizing to push back against the FDA’s overreach and defend your right to choose the treatment that works best for you. We’re hard at work on a white paper that will set out strategies that we believe will protect access to NDT in the short-, medium- and long-term — regardless of which administration is in power. We’re also working to bring together the diverse range of citizens, consumers and practitioners. In the meantime, please send this critical Action Alert to the FDA and your representative in Congress.
