Generally, thyroid replacement treatment is to be taken for life. SYNTHROID should not be used to treat noncancerous growths or enlargement of the thyroid in patients with normal iodine levels, or in cases of temporary hypothyroidism caused by inflammation of the thyroid gland (thyroiditis). USE. SYNTHROID® (levothyroxine sodium) tablets, for oral use is a prescription, man-made thyroid. Generally, thyroid replacement treatment is to be taken for life. SYNTHROID should not be used to treat noncancerous growths or enlargement of the thyroid in patients with normal iodine levels, or in cases of temporary hypothyroidism caused by inflammation of the thyroid gland (thyroiditis). USE. SYNTHROID® (levothyroxine sodium) tablets, for oral use is a prescription, man-made thyroid. Generally, thyroid replacement treatment is to be taken for life. SYNTHROID should not be used to treat noncancerous growths or enlargement of the thyroid in patients with normal iodine levels, or in cases of temporary hypothyroidism caused by inflammation of the thyroid gland (thyroiditis). USE. SYNTHROID® (levothyroxine sodium) tablets, for oral use is a prescription, man-made thyroid. Ideally, levothyroxine should be the only medication taken at bedtime. Just as with morning dosing, it is best to avoid co-administration with other medications such as statins, blood pressure drugs, and metformin. If you must take other medications that must be taken in the evening, consider adjusting the timing of these medications so you take them with dinner, leaving four hours afterward. Find patient medical information for levothyroxine oral on WebMD including its uses, side effects and safety, interactions, pictures, warnings and user ratings. “There are patients who have taken DTE for many decades and are reluctant to consider a change.” 100–200 mcg l-T 4 “The difficulties that led to the development of LT 4 as a replacement preparation, namely inconstant and subpotent desiccated thyroid tables, have largely been obviated by new USP standards for quantitation of T 3 and T 4 in DTE tabs.” BMR = basal metabolic rate; DT. Does SYNTHROID Interact with other Medications? Severe Interactions. These medications are not usually taken together. Consult your healthcare professional (e.g., doctor or pharmacist) for more. DESCRIPTION. SYNTHROID (levothyroxine sodium tablets, USP) contain synthetic crystalline L-3,3',5,5'- tetraiodothyronine sodium salt [levothyroxine (T 4) sodium].Synthetic T 4 is identical to that produced in the human thyroid gland.Levothyroxine (T 4) sodium has an empirical formula of C 15 H 10 I 4 N NaO 4 • H 2 O, molecular weight of 798.86 g/mol (anhydrous), and structural formula as shown: Generally, thyroid replacement treatment is to be taken for life. SYNTHROID should not be used to treat noncancerous growths or enlargement of the thyroid in patients with normal iodine levels, or in cases of temporary hypothyroidism caused by inflammation of the thyroid gland (thyroiditis). USE. SYNTHROID® (levothyroxine sodium) tablets, for oral use is a prescription, man-made thyroid. Generally, thyroid replacement treatment is to be taken for life. SYNTHROID should not be used to treat noncancerous growths or enlargement of the thyroid in patients with normal iodine levels, or in cases of temporary hypothyroidism caused by inflammation of the thyroid gland (thyroiditis). USE. SYNTHROID® (levothyroxine sodium) tablets, for oral use is a prescription, man-made thyroid.