FDA’s Unexpected Shift on Animal-Derived Thyroid Medications

Recently, the FDA experienced an intriguing shift, showcasing the influence of the “Make America Healthy Again” movement, especially regarding its emphasis on “natural” remedies.

Last Thursday, the agency expressed concerns regarding unapproved thyroid medications derived from animal tissues. This came after receiving complaints and reports of adverse events linked to these products. The FDA indicated it would take action against these medications, but not immediately, allowing patients time to transition to alternative treatments.

“The agency encourages patients using these unapproved animal-sourced thyroid medications to consult with their doctors,” the FDA noted.

While such warnings are routine for the FDA, what followed was a wave of social media outrage.

However, on Wednesday evening, FDA Commissioner Marty Makary appeared to pivot, announcing on social media that the FDA was dedicated to pursuing the first approval for desiccated thyroid extract, contingent on ongoing clinical trials. “In the meantime, we will ensure access for all Americans,” he stated.

Just moments later, Health Secretary Robert F. Kennedy Jr. chimed in on the platform, praising Makary’s approach to integrating scientific standards with practicality.

Understanding Animal-Derived Thyroid Medications

The thyroid gland, a small organ at the front of the neck, is essential for regulating the body’s energy usage by producing thyroid hormones. Insufficient hormone production can lead to hypothyroidism, resulting in symptoms like unexplained weight gain, fatigue, sensitivity to cold, and mood changes, as outlined by the Mayo Clinic. This condition is more prevalent in women.

The typical treatment involves hormone replacement therapy, where patients take medications containing synthetic hormones like levothyroxine or liothyronine, or a mix of the two.

Some individuals, though, opt for animal-derived thyroid pills. This may be due to a lack of efficacy from synthetic versions or a preference for alternatives marketed as natural, according to Dr. Michael Weintraub from NYU Langone Health.

These unapproved pills, made from dried pig thyroids, include brands like Armour Thyroid and Nature-Thyroid. Around 1.5 million people in the U.S. were prescribed these medications last year.

The FDA has stated that these animal-derived drugs could contain impurities leading to infections and inconsistent hormone levels, which poses risks for patients. Taking too much or too little could have adverse effects.

Public Reaction

Following the FDA’s warnings, medical professionals and patients voiced their concerns on social media.

One post from functional medicine doctor Will Cole warned, “FDA to ban natural desiccated thyroid medications, relied upon by millions who don’t respond well to syntheses.”

Dave Asprey, founder of a supplement brand, shared his positive experience with natural thyroid extract after unsuccessful attempts with synthetic medications. Dr. Robert Malone, an anti-vaccine advocate recently appointed to a vaccine advisory panel, expressed his dismay at the FDA’s actions, especially regarding postmenopausal women.

Andrew Nixon from the Department of Health and Human Services didn’t respond about whether Makary’s announcement was influenced by the backlash. When asked about the FDA’s future actions, he reiterated that there would be no immediate steps against manufacturers to ensure patient transition time.

Nixon added that more details would emerge as clinical trial results are published.

It remains unclear which clinical trials were being referenced. There’s a note about a trial initiated by Walter Reed National Military Medical Center, though it’s currently marked as “unknown.” Allergan completed their own trial comparing their product to a synthetic hormone in 2021.

A Safety Perspective on These Pills

Dr. Pieter Cohen from Harvard Medical School supported the FDA’s initial warnings, highlighting the risks associated with unregulated animal-derived pills.

The FDA-approved synthetic drugs usually either replace T4 or T3 hormones, and manufacturers must adhere to strict dosing regulations.

Animal-derived pills, although they contain similar hormones, lack such regulation, resulting in unpredictable hormone levels.

Cohen emphasized the potential long-term health risks associated with improper dosing, noting that both too much and too little can lead to significant health issues.

Weintraub mentioned that even small variations in thyroid hormone levels can cause substantial effects, pointing out that pigs have notably higher levels of T3 compared to humans.

He conveyed concerns about potential heart rhythm issues and bone health risks tied to these medications.

On the other hand, Dr. Susan Spratt of Duke Health remarked that it would be unjust for the FDA to abruptly withdraw the animal-derived options without clear evidence of harm.

Spratt noted that these medications have been available for decades, and while she prefers synthetic options, the animal-derived versions provide alternatives for those not responsive to synthetics.

Weintraub concluded that while synthetic drugs may not work for everyone, there’s a more controlled and safer treatment alternative than reverting to animal-sourced thyroids.