*This statement summarizes the third USPSTF recommendations for screening for chlamydial infection and the supporting scientific evidence, and it updates the 1995 recommendations contained in the Guide to Clinical Preventive Services, second edition (1).
Older adults may be more sensitive to the side effects of this drug, especially fast/pounding/irregular heartbeat. Current information shows that this drug may be used during pregnancy. Tell your doctor if you are pregnant because your dose may need to be adjusted. Levothyroxine passes into breast milk but is unlikely to harm a nursing infant.
A: Levothyroxine is a synthetic T4 medication made to mimic the natural T4 hormone produced by the thyroid gland. Levothyroxine is used to treat hypothyroidism or low thyroid levels. Side effects of levothyroxine are hair loss, anxiety, headache, and increased appetite.