Understanding your medication options for treating thyroid disease

The American Thyroid Association estimates that 20 million Americans have some form of thyroid disease, whether it be hyperthyroidism/Grave’s Disease (overactive thyroid), hypothyroidism/Hashimoto’s thyroiditis (underactive thyroid), or thyroid cancer. Yet, up to 60% of those with thyroid disease don’t even know they have it.¹

Thyroid disease is particularly common in women, affecting as many as 1 in 8 in their lifetime.¹ While thyroid disease is typically a life-long condition, there are a number of very effective medications that can help restore proper thyroid hormone levels.

What is the thyroid?

The thyroid is a small, butterfly-shaped gland located in the middle of the lower neck. The gland produces three hormones: triiodothyronine (T3), thyroxine (T4), and calcitonin. These hormones play a major role in regulating essential bodily functions like metabolism, heart rate, body temperature, energy, and blood sugar. When someone has thyroid disease, it means their thyroid isn’t producing the proper amount of thyroid hormones.

Symptoms of thyroid issues

An overactive thyroid (hyperthyroid) is when the thyroid gland makes too many hormones. This can cause side effects such as:

• Irritability
• Nervousness
• Muscle weakness
• Weight loss
• Sleep problems
• Vision problems
• Irregular pulse
• Feeling hot all the time

Conversely, an underactive thyroid (hypothyroidism) is when the thyroid gland doesn’t make enough hormones. This can cause side effects such as:

• Fatigue
• Depression
• Forgetfulness
• Weight gain
• Dry skin
• Feeling cold all the time

Diagnosing thyroid disorders

Thyroid disorders are typically diagnosed via a blood test. The test looks at levels of T4, T3, and thyroid stimulating hormone (TSH). A high TSH, low T3, and/or low T4 are often indicators of hypothyroid and a low TSH, high T3, and/or high T4 are often indicators of hyperthyroid.

Some doctors may look at levels of thyroid antibodies to help diagnose autoimmune thyroid disorders such as Hashimoto’s thyroiditis or Grave’s disease. Thyroid antibodies are made when the immune system mistakenly attacks the thyroid gland, either causing it to produce too many or too few thyroid hormones.

Other diagnostic tests, such as ultrasounds, can help detect goiters (irregular growth of the thyroid gland), thyroid nodules (fluid-filled lumps in the neck), or masses that may be influencing how the thyroid is functioning. An iodine uptake test can help identify causes of hyperthyroidism by tracking how much iodine is absorbed by the thyroid gland.

Medications for treating hyperthyroid

Anti-thyroid medicines called thionamides are the most common treatment for overactive thyroid. They stop the thyroid from producing excess hormones. The main medications are methimazole (Tapazole^®) and propylthiouracil.

Methimazole is typically the first line of treatment because it works quickly and has few side effects. Propylthiouracil is typically the first line of treatment in pregnant women due to the lower risk of birth defects. It usually takes 1-2 months to notice a change in symptoms after starting these medications.

Other treatment options include radioactive iodine treatment, which damages the cells of the thyroid to keep it from producing as many thyroid hormones, and surgery to remove the thyroid gland.

Medications for treating hypothyroid

There are two types of thyroid replacement medications to treat hypothyroidism: synthetic medicine and desiccated thyroid extract (DTE).

• Synthetic thyroid medication is FDA approved and contains a synthetic version of T4. The generic version of this medication is levothyroxine and the brand names include Synthroid^®, Levoxyl^®, Unithroid^®, Tirosint^®. Thyroid medication has a narrow therapeutic index, meaning that the body is sensitive to even small variations in medication. As a result, it’s not recommended to switch between generic and brand-name versions of synthetic thyroid medication. If synthetic T4 isn’t effective, your doctor may prescribe synthetic T3, liothyronine (brand names Cytomel^® and Triostat^®).
• DTE or natural thyroid medication is made from dried, ground thyroid glands from pigs. These medications are not FDA approved and contain both T4 and T3 hormones. The common brand names are Armour Thyroid and NP Thyroid. The process of making DTEs is more complex than synthetic thyroid medication and can often have quality issues or dose inconsistencies. Some batches of DTEs at the same manufacturing facility don’t always have the same hormone levels, often prompting voluntary drug recalls.

Once you start thyroid replacement medication, it can take up to two weeks to notice your symptoms improving and several weeks to experience full symptom relief. If you still experience symptoms after a month of taking thyroid hormone replacement medication, talk to your doctor. They may gradually increase or decrease your medication dose, or suggest switching to a different type of medication to figure out what works best for managing your symptoms.

Let your doctor or pharmacist know if you are pregnant or planning to become pregnant, as it may require a dose change.

How to take thyroid medications

Be sure to read your medication label and any information that comes with your medication. It’s typically best to take thyroid medication first thing in the morning with a full glass of water on an empty stomach, 30-60 minutes before breakfast and away from other medications.

Avoid taking multivitamins or supplements containing iron, calcium, or magnesium within 4 hours of taking thyroid medication because they interfere with proper absorption. It’s also best to avoid coffee within the first hour of taking medication as it can affect absorption, too.

Some medications are processed by the same enzyme in the liver, which can affect how well the thyroid replacement medication works. These include certain cholesterol medications, anti-seizure medications, and testosterone/estrogen based medications. Talk to your doctor or pharmacist about all of the medications you’re taking so you can ensure that you’re getting the full dose of your thyroid medication.

Work with your pharmacist

At Express Scripts® Pharmacy, we understand the challenges of dealing with thyroid disease. Our team of experienced pharmacists have knowledge about thyroid conditions and are available 24/7 to answer any of your questions or concerns.

While thyroid disease is often a lifelong condition, it can be effectively managed with proper medication, and you can enjoy a full and healthy life.

1 American Thyroid Association: General Information/Press Room (accessed May 31, 2023): thyroid.org/media-main/press-room/.