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Synthyroid is a common misspelling of Synthroid (levothyroxine).

What is Synthroid (Synthyroid)?

Synthroid (Synthyroid) is a synthetic thyroid hormone. Thyroid hormones are produced and released by the thyroid gland and regulate the body's metabolism. When the thyroid gland is underactive (hypothyroidism) it does not produce enough thyroid hormone and metabolism slows.

Synthroid (Synthyroid) is taken if your own thyroid gland is not making enough hormone or if you have an enlarged thyroid (a goiter) or are at risk for developing a goiter.

Synthroid (Synthyroid) is also used if your thyroid production is low due to surgery, radiation, certain drugs, or disease of the pituitary gland or hypothalamus in the brain.

Synthroid (Synthyroid) is used to treat certain cancers of the thyroid.

Synthroid (Synthyroid) should not be used to treat obesity or weight problems.

Synthroid (Synthyroid) side effects may include headache, nervousness, trembling, sweating, increased appetite, diarrhea, weight loss or insomnia.

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Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.