*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.
Levothyroxine Side Effects. For the Consumer. In addition to its needed effects, some unwanted effects may be caused by levothyroxine. In the event that any of these side effects do occur, they may require medical attention. Severity: Major. Severity: Minor. Some of the side effects that can occur with levothyroxine may not need medical attention. As your body adjusts to the medicine during treatment these side effects may go away. Your health care professional may also be able to tell you about ways to reduce or prevent some of these side effects.