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SYNTHROID® (levothyroxine sodium tablets, USP). SYNTHROID® is used when the thyroid gland does not produce enough hormone (hypothyroidism). It is also used to treat certain types of thyroid cancer. Do not use SYNTHROID® if you have an allergy to thyroid hormones or any of the ingredients in the tablet, or have an overactive thyroid gland (thyrotoxicosis) of any cause or if you have recently had a heart attack, acute myocarditis (inflammation/ swelling of the heart muscle), or acute pancarditis (general inflammation/ swelling of the heart) or if you have an uncorrected adrenal gland insufficiency, or if you are pregnant and also using medicines to treat an overactive thyroid. To help avoid side effects and ensure proper use, talk to your healthcare professional before you take SYNTHROID®. Talk about any health conditions or problems you may have, including if you are pregnant or plan to become pregnant; have any heart problems, whether or not you have received treatment for them, including a history of heart attack, heart disease or hardening of the arteries; have other medical problems, whether or not you have received treatment for them, including high blood pressure, osteoporosis, blood clotting disorders, a history of thyroid, adrenal and/or pituitary gland problems; have signs or symptoms of psychotic disorders; are switching from a different brand of levothyroxine; are a woman on long-term SYNTHROID® therapy; develop myxedema coma, a medical emergency (a type of severe hyperthyroidism); have malabsorption syndromes (inability to absorb nutrients, vitamins, and minerals from the intestinal tract into the bloodstream); diabetes; surgery; breast-feeding; driving and using machines. Tell your healthcare professional about all the medicines you take, including any drugs, vitamins, minerals, natural supplements or alternative medicines. Possible side effects includes fever, flushing and excessive sweating, restlessness, nervousness, anxiety, rapid changes in emotion, trouble sleeping, temporary hair loss, diarrhea, vomiting, nausea, stomach cramps, changes in menstrual cycle, trouble having a child (impaired fertility), fatigue, headache, muscle weakness, tremors, reduced adult height due to early closure of growth plates in bones, change in appetite, weight gain or loss. These are not all the possible side effects you may have when taking SYNTHROID®. If you experience any side effects not listed here, tell your healthcare professional. in appetite, weight gain or loss. These are not all the possible side effects you may have when taking SYNTHROID®. If you experience any side effects not listed here, tell your healthcare professional.

SYNTHROID® is a registered trademark of Viatris Healthcare GmbH, used under permission by BGP Pharma ULC, a Viatris company.
VIATRIS and VIATRIS & Design are registered trademarks of Mylan Inc., used under permission by BGP Pharma ULC, a Viatris company.

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