If you have been diagnosed with low thyroid function, or hypothyroidism, you and your doctor have a number of medications to choose from.
As a Naturopathic Physician, my focus is to choose the medication that fits your needs, to individualize your prescription so that you are adequately treated and your symptoms are relieved.
The purpose of this article is to discuss natural thyroid medications so you can make an informed decision.
Natural vs Synthetic
Natural thyroid medications are prescription medications made from the thyroid glands of pigs raised specifically for this purpose. You might find them named
- Desiccated thyroid
- Glandular thyroid
- Natural Desiccated Thyroid
This is the only thyroid medication that contains all four thyroid hormones that our bodies make: T4, T3, T2, and T1. In addition, its iodine, thyroglobulin protein and glandular tissue content have useful functions in the body.
Trade names of this Natural Desiccated Thyroid include:
- Acella – NP Thyroid
- Armour thyroid
- WP Thyroid
In addition, compounding pharmacies may use whole desiccated thyroid porcine glandular in their individualized prescriptions.
Most mainstream doctors prescribe a thyroid medication that is synthesized from chemicals in a lab and contains the hormone T4 only. This is available in both trade name brands and generic forms. Synthroid is in the top 10 most commonly prescribed medications. Common forms include:
In addition, synthesized T3 hormone is available by prescription as well as compounded. The brand name is Cytomel and the generic form is known as liothyronine.
Advantages of Natural Desiccated Thyroid
- A natural mix of all 4 thyroid hormones T4, T3, T2, T1
- T4 is the predominant thyroid hormone produced by our thyroid glands, but it is minimally active until converted to T3
- A small amount of the metabolically active T3 helps people who don’t effectively convert their T4 into T3
- Contains thyroglobulin protein which slows the breakdown of T3, the active hormone so that it will keep you going all day without having to dose again during the day
- T2 has been found to play a role in metabolism and fat burning
- The glandulars in the NDT can help strengthen and rebuild you own thyroid gland, provided you still have it
- Also one grain NDT contains 120 micrograms of iodine. The adult RDA is 150 mcg, with the WHO (World Health Organization) recommending 220 mcg for pregnant women.
- Relatively low price – pigs thyroid glands are sold at a low cost to manufacturers
- No one can patent a pig thyroid gland, so name brands are already at generic prices
Disadvantages of Natural Desiccated Thyroid
- Comes from a pig, which is objectionable to vegetarians, Orthodox Jews and other religious groups, and others who find it distasteful
- A smaller range of dosages available than the synthetic, so sometimes a combination of pills must be used to get in-between dosages
- At times, there has been a “shortage” of natural raw materials, limiting its availability
- Many mainstream doctors will flat-out refuse to prescribe it
Issues which are debatable as advantages / disadvantages
The human thyroid gland makes a ratio of T4 to T3 of approximately 10 to 1. The pig gland in NDT contains a ratio of 5 to 1. This makes an excess proportion of T3. Some patients can use this higher proportion if they have trouble converting T4 to T3. In addition, there is some evidence that in cells, the proportion of T4 to T3 is closer to the 5 to 1.
The first thyroid hormone supplements came from animal glandular tissue. At that time, the potency was determined by measuring its iodine content, because that was the best technology could do.
In 1955, Synthroid first came to the market. In an aggressive marketing campaign, it was promoted as new and modern and the desiccated thyroid was portrayed as old fashioned and inconsistent from batch to batch. Then there was a report in a major medical journal of one patient who was severely under-treated due to the inconsistency of the natural desiccated thyroid. This sealed the fate of NDT in some physician’s minds and showed the shining advantage of the money-maker Synthroid.
All thyroid hormone medication manufacturers must follow the guidelines of the United States Pharmacopeia (USP), a highly respected authority which sets the standards. With the advent of new technologies in the mid-1980’s, natural desiccated thyroid manufacturers could now measure the actual amounts of T3 and T4 in their pills. So now there is absolutely no difference in standardization between synthetic and natural forms of thyroid, as long as the manufacturers are adhering to the standards.
In fact, the USP standard allows a 10% variation in T4 and 10% variation in T3 in the manufacture of thyroid medications. This can account for some of the brand variations. And look at the history of recalls on medications due to mistakes: synthroid has had several and so has Armour.
RLC labs stands out from all the other manufacturers in that their in-house policy is to only allow less than or equal to 2% variation in the T3 and T4. RLC labs tablet natural desiccated thyroid into
- WP Thyroid
And they have had no recalls.
Natural Desiccated Thyroid and Autoimmune Thyroid
It is thought in some circles that Natural Desiccated Thyroid will aggravate patients with Hashimoto’s autoimmune thyroid condition. The thinking is that there is an immune attack on the enzyme thyroperoxidase and the protein thyroglobulin when it is released from the NDT, perpetuating the autoimmune attack.
Wow! This could be huge and sounds viable in theory!
I have had a few patients who did not respond well to NDT, but I was not able to determine if it aggravated an autoimmune attack or if there was some filler ingredient they did not tolerate.
A literature review has not shown any evidence of the theory, though. In fact, one citation showed NDT was actually beneficial because it induced tolerance, calming the immune attack, instead of aggravating the condition.
This discussion will continue in another article about the issue of fillers in NDT medications. Fillers are what makes the difference between brands.