Over-active thyroids are extremely common, and appears most frequently in women.
Overactive thyroid could be temporary (thyroiditis, pregnancy) from an illness or a medication, or it could be permanent (Graves’ disease or toxic nodules) but there are several ways we can treat these conditions:
- Medication: drugs called methimazole and propylthiouracil can block production and release of thyroid hormone, as well as reduce its conversion to the active form.
- Radioactive iodine: a pill of an iodine isotope can “burn out” an overactive gland, or the overactive nodules inside of an otherwise normal gland.
- Surgery: available to people who are unable or unwilling to take the medication or radioactive treatments, or for those whose goiter is so big it’s obstructing breathing or swallowing.
- RFA: radiofrequency ablation of a “toxic nodule” can correct the hyperthyroidism without harming the rest of the thyroid tissue.
I have an overactive thyroid but I feel great so what’s the big deal?
What’s the Big Deal?
Even a very slightly overactive thyroid can “chip away” at our muscle mass, bone density and heart health over time.
What’s the Deal with Antibodies?
Graves’ disease can be detected by Thyroid Stimulating Immunoglobulin (TSI) or Thyroid Receptor Antibody (TRAb):
- These antibodies can cause complications with the eye including redness, swelling, difficulty moving/closing the eye, bulging eyes and vision changes.
- With medical therapy Graves’ can go into remission over time.
Hashimoto’s thyroiditis can be detected by Thyroid Peroxidase Antibody (TPO). Sometimes this causes an initial phase of overactivity before hypothyroidism sets in.
Am I at Risk for Other Autoimmune Problems?
Technically, yes. Sometimes, autoimmune “Birds of a feather flock together.”
How Can I Tell if My Thyroid is Overactive?
Classic symptoms include: anxiety, enlarged thyroid, sweating, diarrhea, increased appetite but unintentional weight loss, reduced periods, protruding eyes, peeling/splitting nails, heart palpitations, feeling hot all the time.
The important thing to remember is that thyroid symptoms represent a spectrum of disease depending on how altered the hormone levels are, so it’s important to look at the whole picture and address other causes for those symptoms too.
Medications for Overactive Thyroid
Both methimazole and propylthiouracil (PTU) act to block thyroid hormone production and release of hormone from the gland. PTU also reduces the conversion of T4 to T3 in your body’s cells:
- Methimazole is the first choice agent, unless you are pregnant or you cannot tolerate methimazole.
- Each medication carries a rare (approximately 1/3000) risk of agranulocytosis, which means that the body can’t produce the right blood cells. So if you take this medication and have a fever or acute illness, you must have your blood drawn THAT DAY to confirm you are making the right white cells.
- If you have agranulocytosis, it is reversible by discontinuing the medication.
How Do We Know if Treatment is Adequate?
- We check TSH and FT4 again in about 8 weeks.
- When we hit the sweet spot with levothyroxine or methimazole/PTU dosing, the TSH and FT4 numbers will go back to their normal ranges.
- If symptoms persist despite normal thyroid numbers, we have to “go back to the drawing board” to consider other causes for the symptoms.
- Note: the supplement biotin is known to interfere with certain thyroid tests and can produce confusing results. If you are on any supplement that contains biotin, stop for 7 days prior to having labs drawn.
Dietary Strategies or Supplements
- At this time there are no widely accepted dietary strategies to help thyroid function.
- Gluten – there is a lot of anecdotal evidence about gluten sensitivity and Hashimoto’s but no randomized trials.
- Selenium – may help reduce inflammation associated with autoimmune thyroiditis.
- Iodine – we have plentiful access to dietary iodine in the United States. Taking a “thyroid support” supplement or elemental iodine can actually INDUCE or WORSEN thyroid conditions.
Resources
- American Thyroid Association: https://www.thyroid.org/thyroid-information/
- Mayo Clinic: www.mayoclinic.com