Part 3: Little known facts about thyroid medications

At Texas Metabolic Centers, we usually try supplements and lifestyle changes before we resort to medications for hypothyroidism.  But when medications are needed, we have a variety of medications from which to choose.  The least expensive, and most prescribed in other medical clinics, is Synthroid or Levothyroxine.  However, we find that many people find this medication to be inadequate in relieving their symptoms.  Why?  It could be that it's not taken correctly (on an empty stomach, in the morning, 1-2 hours before eating or drinking anything), it’s synthetic, that the body needs both T4 and T3, or that the “fillers”(inactive ingredients) in the medications don’t react well with the patient.  Whatever the case, there are other thyroid medications to consider.  Here is a list:

1.    Synthroid (levothyroxine) 

Contains synthetic T4 (inactive thyroid hormone), which the body is responsible for converting to active thyroid hormone (T3).  However, before the invention of Synthroid in 1955, most physicians would use dessicated thyroid gland (usually from pigs or cows). 

a.    Pros: Inexpensive, covered by insurance.  Delivers a consistent dose of T4.

b.    Cons: It’s synthetic.  Patients may not convert the T4 to T3 efficiently, because it is not “bioidentical” to what the thyroid naturally makes.  Patients may also react to the inactive ingredients (for example, it contains lactose).  Cannot be guaranteed to be gluten free.

c.     Fillers/Inactive ingredients: acacia, confectioner’s sugar with cornstarch, lactose monohydrate, magnesium stearate, povidone, talc, and food dyes (depending on strengths, e.g. FD&C Yellow No. 6 in 25 mcg tablets, FD&C Red No. 40 and FD&C Blue No. 2 in 75mcg strength, etc)

2.    Levoxyl (also levothyroxine)

Also a synthetic T4, like Synthroid. Fillers/inactive ingredients tend to be less problematic.

a.    Pros: Inexpensive, covered by insurance.  Delivers a consistent dose of T4.  Gluten free.

b.    Cons: It’s synthetic.  Patients may not convert the T4 to T3 efficiently, because it is not “bioidentical” to what the thyroid naturally makes.  Patients may also react to the inactive ingredients (for example, it contains lactose).

c.     Fillers/Inactive ingredients: Microcrystalline cellulose, croscarmellose sodium, magnesium stearate, calcium sulfate dihydrate and sodium bicarbonate, along with color additives depending on the tablet strength

3.    Cytomel:

Synthetic T3.  Usually need to take this in combination with T4 or a combination of T3/T4.

a.    Pros: The body doesn’t need to break it down into active form, since it’s already activated.  Gluten free.

b.    Cons: Short lasting (so need to take twice a day).  Patients with GI issues could react to the inactive ingredients.

c.     Fillers/Inactive Ingredients: calcium sulfate, gelatin, a starch usually from corn or rice, stearic acid, sucrose and talc.

4.    Armour

A natural thyroid hormone replacement, derived from porcine thyroid glands.  Contains both T4 and T3. 

a.    Pros: Natural.  It has both T4 and T3. Doesn’t contain lactose (like Nature-throid)

b.    Cons: Contains pork-based product, so can be an issue in someone who doesn’t consume pork.  People may react to fillers.

c.     Fillers/Inactive ingredients: calcium stearate, dextrose, microcrystalline cellulose, sodium starch glycolate, and opadry white.

5.    Nature-Throid

One of the first released thyroid hormone replacements (released in 1930s).  Like Armour, this is a natural thyroid hormone replacement, with both T4 and T3, as well as thyroid cofactors (T1, T2, calcitonin, iodine) in trace amounts.  Also derived from porcine thyroid gland.

a.    Pros: Natural.  Has both T4 and T3. Gluten free.

b.    Cons: Contains pork-based product, so can be an issue in someone who doesn’t consume pork.  Contains lactose.

c.     Fillers/Inactive ingredients: colloidal silicon dioxide, dicalcium phosphate, lactose monohydrate (very small amount – 5mg in 1 grain, vs 15000mg in 8oz of milk), magnesium stearate, microcrystalline cellulose, croscarmellose sodium, stearic acid, Opadry II

6.    Westhroid

Exact same formulation as Nature-throid, but different fillers/inactive ingredients.

a.    Pros: Natural.  Has both T4 and T3. Gluten free.

b.    Cons: Limited strength amounts.  Contains pork-based product, so can be an issue in someone who doesn’t consume pork.  Contains lactose.

c.     Fillers: Colloidal silicon dioxide, dicalcium phosphate, magnesium stearate, microcrystalline cellulose, croscarmellose sodium, stearic acid, opadry clear tablet coating

7.    WP Thyroid

Purported to be the most pure pre-made medication for hypothyroidism.  Only has 3 all-natural inactive ingredients.

a.    Pros: Natural.  Has both T4 and T3.  Gluten free

b.    Cons: Limited strength amounts.  Contains pork-based product, so can be an issue in someone who doesn’t consume pork.  Contains lactose.

c.     Fillers/Inactive ingredients: inulin from chicory root, MCT oil from coconut, lactose

8.    Compounded formulations. 

Dependent on compounding pharmacy, and practitioner discretion for dosages. 

a.    Pros: Tailor made for patients.  Natural.

b.    Cons: More expensive.  Insurance often won’t cover.

c.     Fillers/inactive ingredients: Vary depending on pharmacy.

 

At the end of the day, however, it is important to treat the person and not the numbers. Remember the previous posts?  MANY vitamin deficiencies and lifestyle factors affect thyroid hormone production and utilization.  Medication can be used when there are symptoms, but no lab abnormalities, but it is important to treat the root cause of the thyroid’s dysfunction.  Once your body gets used to receiving thyroid hormone from a pill, there is a risk (not high, but not low) that the thyroid may decide to stop producing thyroid hormone and you’re stuck on medication for life.  So address the underlying causes before jumping straight to medications! 

And remember that if you’re on thyroid hormone replacement already, you can still make sure the body uses it efficiently, AND you may even be able to come off of it if you address the root cause of the thyroid dysfunction!

Contact Texas Metabolic Centers if you’re interested in learning more about your thyroid health. We can help!

 

All information obtained from www.pdr.net, and www.rxlist.com