Explaining the Different Thryroid Medications: Armour, Desiccated, Levothyroxine, & Liothyronine
by Jasen Bruce
With the ever increasing price of the brand “Armour Thyroid”, which is a popular thyroid medication we prescribe, I wanted to take a moment to explain the different thyroid medications. We have options for our patients which are a better cost and it is important for you to understand the differences in medication in order to both save money and more importantly receive proper treatment.
The thyroid consists of two hormones known as triiodothyronine (or T3) and it’s prohormone thyroxine (or T4). In conventional medicine many patients diagnosed with hypothyroidism are only prescribed Synthroid/Levothyroxine (T4) by itself. T4 is a prohormone which must convert to the active T3 hormone for the body to properly respond. Some people have an issue converting T4 into T3 and therefore still experience symptoms of hypothyroidism despite showing normal T4 levels. Achieving optimal T3 levels is an important outcome necessary for the effective treatment of hypothyroidism and related symptoms.
Alternatively patients can be prescribed a compounded combination of T3 and T4 to treat hypothyroidism. There are two types of T3 and T4 medications available at our compounding pharmacy; Desiccated T3/T4 combinations and ‘synthetic’ T3/T4 combinations. Desiccated thyroid is what people consider ‘natural’ or ‘bio’ thyroid. This is because desiccated thyroid is extracted from animal thyroid gland tissue. The most common and the type we use is extracted specifically from porcine (pig) tissue, which is believed to be most similar to a human. “Armour” thyroid is a brand name for desiccated thyroid. Desiccated and Armour thyroid are one in the same.
Synthetic thyroid (t3/t4) comes in the form of Levothyroxine (T4) and Liothyronine sodium (T3). Technically even desiccated thyroid, despite being known as natural, still goes through a synthesis in a lab. Common brand names for synthetic versions are “Cytomel (t3)” and “Synthroid (t4)”.
Both desiccated and synthetic T3 and T4 is available as a compounded generic at most compounding pharmacies. Compounded thyroid is much cheaper than using the brand name thyroids like Armour. Remember, Desiccated is the same thing as Armour- Armour is just a brand name for generic porcine desiccated thyroid. When it comes to compounded ‘synthetic’ (liothyronine/levothyroxine) thyroid, unlike with desiccated pharmacists can customize the ratio of T3 and T4 therefore allowing the doctors to adjust the dosage to the smallest detail based upon individual patient response. The nice thing about compounded thyroid medications is that both T3 and T4 are combined in a single capsule whereas the brand name comes in only T3 (Cytomel) or T4 (Synthroid) individually as a tablet and is more expensive.
There is a place for both types of thyroid combination medications. Some patients respond well to desiccated thyroid while others need a combination of liothyronine sodium t3/levothyroxine t4 to respond to treatment. For example, desiccated and Armour thyroid comes in a pre-determined ratio of T3 and T4, usually 4:1 ratio of T4 to T3. As mentioned above, compounded liothyronine sodium/levothyroxine combination can be customized which some patients may need. Another example of why someone may respond to one over the other; since Desiccated thyroid is 4:1 ratio of T4 to T3 and humans are generally 11:1, there may be some who do not respond to desiccated and need liothyronine sodium t3 and levothyroxine t4 at a specific ratio to restore thyroid levels successfully.
There are many patients who respond very well to desiccated thyroid and therefore prefer to have the more ‘natural’ form. Medically, both are found to be safe long term when properly administered and monitored by a trained doctor. Therefore the preferred type to use depends on what works best for the patient.