Levothyroxine, a synthetic version of the thyroid hormone known as T4, is at or near the top of the list of most prescribed medications. Millions of Americans need to take this medication because their own thyroid glands don’t produce enough. While the majority of people on levothyroxine do pretty well on it, some people find they still have symptoms of an underactive thyroid. Among them, a number have reported that they feel better on desiccated thyroid gland such as Armour. It comes as a shock, though, to learn the FDA has not approved these old-fashioned medications.
Trying Out Armour for Hypothyroidism:
Q. My doctor is cool with anything reasonable that I want to try. So when I asked for a scrip for Armour Thyroid instead of the levothyroxine (Levoxyl) I’ve been taking for years, he agreed. I have been on Levoxyl ever since my thyroid was removed to treat Graves’ disease.
I’m on Medicare and my insurance denied it because it is not FDA approved. It’s inexpensive, so I paid cash for it, just $20.
My poor daughter, who has hypothyroidism due to Hashimoto’s, asked her endocrinologist and the reaction was swift. “NO! I don’t prescribe Armour to anyone I care about. Tell your mother not to take it.”
I’m taking it anyway, and in another six weeks I’ll be getting labs done. If it’s working, great. If not, I return to Levoxyl. I haven’t noticed any difference, but I’ll go with the bloodwork.
Are you aware the FDA has not approved this? Apparently, it’s some kind of control over how much of each hormone (T3 and T4) the pill contains.
Why the FDA Has Not Approved Desiccated Thyroid Extract:
A. Armour Thyroid and other brands of desiccated (dried) thyroid extract (DTE) are made from pig thyroid glands. Before there was synthetic thyroid (Synthroid or levothyroxine), doctors relied upon DTE to treat people with underactive or missing thyroid glands. These products were grandfathered into pharmacy practice.
According to the official prescribing information for Armour Thyroid,
“This drug has not been found by FDA to be safe and effective, and this labeling has not been approved by FDA.”
However, the description of the drug specifies exactly how much T3 (liothyronine) and T4 (levothyroxine) each grain of thyroid extract contains. We suspect that the reason FDA has not approved these drugs may be linked to the cost of applying for New Drug Approval. Quality control in the mid-20th century was lax, and the drug got a bad reputation among endocrinologists for that reason. We understand that has improved, but some experts are still leery of prescribing it. Nonetheless, endocrinologists should be personalizing thyroid treatment (Frontiers in Endocrinology, July 9, 2019).
Most people do well on medications such as Levoxyl or Synthroid with levothyroxine alone. Some, however, report that they feel much better on Armour or another desiccated thyroid extract, presumably because it contains T3 as well as T4. You can learn more about this and why it’s important in our eGuide to Thyroid Hormones. You may also wish to listen to our interview with Dr. David Cooper, Director of the Thyroid Clinic at Johns Hopkins. It is Show 1162: How to Treat Common Thyroid Problems. In it, we discuss Graves’ disease and hyperthyroidism as well as Hashimoto’s and hypothyroidism. We also discussed how genetic variations might explain who feels better on desiccated thyroid extract in Show 1096: What You Need to Know About Treating Thyroid Disease.