What You Need to Know About Synthdroid

If you or your child are suffering from thyroid conditions, your doctor may have recommended Synthroid.

What is Synthroid?

Synthroid is a brand name of levothyroxinen artificial hormone used to treat hypothyroidism, a condition in which the thyroid does not make enough hormone.1

What does it do? Does Synthroid work?

Low levels of thyroid hormone, hypothyroidism, can cause lack of energy, weight gain, slow speech, hair loss and other symptoms. Levothyroxine is also used to treat congenital hypothyroidism (cretinism) and goiter (enlarged thyroid gland).

A study of pediatric patients found Synthroid reduced thyroid volume in younger patients and in reducing goiter (a swelling on the thyroid) in older children and teens. 2

What should I ask my doctor about before I decide to take Synthroid?

Large doses of thyroid hormones can cause fatal toxicity, especially when taken with appetite suppressant medications. Synthroid should not be used for weight loss.3

Synthroid may worsen cardiovascular conditions and can affect bone density in women. 4

Effects of overdose can include cerebral embolism, shock, coma, and death and seizure has been reported in a child.5

Synthroid may react with a long list of other medications, antidepressants, some cardiac medications, anti-diabetic medications, some drugs prescribed to treat arthritis pain and antacids.6

What if I’m already taking Synthroid?

You should always talk to your doctor before stopping any prescription medication. Talk to your doctor if you experience any adverse effects or if you are concerned about side effects.

Learn everything that you can about Synthroid before you start taking it.

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1 Levoxthyroxine is a synthetic chemical that copies a naturally occurring thyroid hormone that regulates metabolism. http://www.synthroid.com/
2 Journal of Clinical Endocrinology and Metabolism, Svensson et al., “Levothyroxine Treatment Reduces Thyroid Size in Children and Adolescents with Chronic Automimmune Thyroiditis,” (May 2006) http://jcem.endojournals.org/content/91/5/1729.long
3 Food and Drug Administration, Synthroid label (August 2005, retrieved 20 August 2012), http://www.accessdata.fda.gov/drugsatfda_docs/label/2008/021402s011lbl.pdf
4 Ibid.
5 Ibid.
6 Ibid.