In the elderly and in patients with cardiovascular disease, SYNTHROID should be initiated at lower doses than those recommended in younger individuals or in patients without cardiac disease. Patients with coronary artery disease who are receiving SYNTHROID should be closely monitored for cardiac arrhythmias during surgical procedures. For pregnant patients with pre-existing hypothyroidism, measure serum TSH and free-T4 as soon as pregnancy is confirmed and, at minimum, during each trimester of pregnancy. In pregnant patients with primary hypothyroidism, maintain serum TSH in the trimester-specific reference range.
DAW codes are codes a pharmacy uses when filling your patient’s prescription. DAW-1 indicates that substitution is not allowed, based on the prescriber’s preference, and ensures your synthroid sommeil patient will receive the treatment you prescribe. It also helps your patient pay the lowest possible price for the product you write if it is billed through insurance. That’s because substitutions can be made at the pharmacy if the prescription is not properly protected with the Dispense as Written (DAW) state-specific language. Some key points that I discuss with the patients during appointments are, one, is that this is an open conversation.
I go over with them the fact that they should check the label at the pharmacy, on the bottle, to make sure it says brand-name SYNTHROID and not generic levothyroxine. And in many cases, to also pop the top off the bottle while they are at the pharmacy counter and look at the pills and make sure they have SYNTHROID embossed on those tablets. So, it’s not just treating a number and following the TSH, it’s also making sure that the patient’s symptoms have improved.
Store at 25°C (77°F); excursions permitted to 15°-30°C (59°-86°F) see USP Controlled Room Temperature. Long-term carcinogenicity studies in animals to evaluate the carcinogenic potential of levothyroxine have not been performed. Studies to evaluate mutagenic potential and animal fertility have not been performed.
Dosing adjustments are based on an assessment of the individual patient's clinical and laboratory parameters (see PRECAUTIONS - Laboratory Tests). The major pathway of thyroid hormone metabolism is through sequential deiodination. Approximately eighty-percent of circulating T3 is derived from peripheral T4 by monodeiodination. The liver is the major site of degradation for both T4 and T3, with T4 deiodination also occurring at a number of additional sites, including the kidney and other tissues.
Metabolic signals such as ghrelin, insulin or glucagon modulate insulin sensitivity, glucose tolerance, lipid metabolism, vascular hemostasis, and even immune responses120,121. Insulin is well known for its anabolic effect and its participation on fat and carbohydrate metabolism. Similar to adipokines, insulin also shows a diurnal pattern and regulates enzymes controlling triglyceride metabolism122.
Please see the additional Important Safety Information at the end of this video, including the BOXED WARNING regarding inappropriate treatment for obesity or for weight loss. Levothyroxine is one of the ten NTI drug classes most commonly prescribed. These medications are those where small changes in the dose or blood concentration may lead to serious therapeutic failures and/or adverse drug reactions.
Treat patients with adrenal insufficiency with replacement glucocorticoids prior to initiating treatment with SYNTHROID see Contraindications (4). Since some more severely affected children may become clinically hypothyroid when treatment is discontinued for 30 days, an alternate approach is to reduce the replacement dose of levothyroxine by half during the 30-day trial period. If, after 30 days, the serum TSH is elevated above 20 mU/L, the diagnosis of permanent hypothyroidism is confirmed, and full replacement therapy should be resumed.
Testosterone’s conversion to dihydrotestosterone further enhances this inhibitory effect, reducing CRH and AVP mRNA expression in the PVN, decreasing POMC mRNA in the pituitary, and enhancing GR-mediated feedback83. Because of the increased prevalence of cardiovascular disease among the elderly, initiate SYNTHROID at less than the full replacement dose see Dosage and Administration (2.3) and Warnings and Precautions (5.2). Atrial fibrillation is the most common of the arrhythmias observed with levothyroxine overtreatment in the elderly. Rapid restoration of normal serum T4 concentrations is essential for preventing the adverse effects of congenital hypothyroidism on cognitive development as well as on overall physical growth and maturation. Levothyroxine is generally continued for life in these patients see Warnings and Precautions (5.1). Initiation of thyroid hormone therapy prior to initiating glucocorticoid therapy may precipitate an acute adrenal crisis in patients with adrenal insufficiency.
Serum TSH levels should be monitored and the SYNTHROID dosage adjusted during pregnancy. Since postpartum TSH levels are similar to preconception values, the SYNTHROID dosage should return to the pre-pregnancy dose immediately after delivery see Dosage and Administration (2.3). Biotin supplementation may interfere with immunoassays for TSH, T4, and T3, resulting in erroneous thyroid hormone test results. Stop biotin and biotin-containing supplements for at least 2 days before assessing TSH and/or T4 levels see Drug Interactions (7.10).
