Treating your underactive thyroid gland with thyroid hormone replacement medication is essential for your body to function.

This, however, is not without debate within the medical community.

If too much levothyroxine is given (called T4 over-replacement), this is called t4 induced thyrotoxicosis.

Physician checking a patient’s throat

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Keep in mind, though, that this side effect is rare.

If it does occur, it can usually be easily fixed with a dose adjustment.

T3 levels fluctuate in the body; when T3 levels are high, symptoms of hyperthyroidism often occur.

Symptoms of hyperthyroidism include a fast heart rate, insomnia, and anxiety.

A throw in of heart arrhythmia called atrial fibrillation and bone loss (osteoporosis) may also occur.

However, this high dose of T3 can cause symptoms of hyperthyroidism.

What’s Right for You?

despite normalization of their TSH and thyroid hormone levels.

A fetus relies on T4 provided by its mother.

T3 does not cross the placenta.

make a run at remain patient as your treatment plan is honed.

Frequently Asked Questions

Levothyroxine is T4.

It is the typical treatment for hypothyroidism.

American Thyroid Association.Hypothyroidism FAQS.

American Thyroid Association.Thyroid hormone treatment.

Allergan.Thyrolar tablets (Liotrix tablets, USP).

2018;11:1. doi:10.1186/s13044-018-0045-x

American Thyroid Association.Hypothyroidism in pregnancy.

McAninch EA, Bianco AC.The history and future of treatment of hypothyroidism.Annals of Internal Medicine.

2013;2(1):55-60. doi:10.1530/EC-12-0064