SYNTHROID- levothyroxine sodium tablet
Start at a lower starting dosage and increase the dosage every 4 to 6 weeks as needed based on clinical and laboratory response. Inquire whether patients are taking biotin or biotin-containing supplements. If so, advise them to stop biotin supplementation at least 2 days before assessing TSH and/or T4 levels see Dosage and Administration (2.4) and Drug Interactions (7.10). The dose of this medicine will be different for different patients. The following information includes only the average doses of this medicine.
- In pregnant patients with primary hypothyroidism, maintain serum TSH in the trimester-specific reference range.
- This will allow your doctor to see if the medicine is working properly and to decide if you should continue to take it.
- If you miss a dose of this medicine, take it as soon as possible.
- Follow all directions on your prescription label and read all medication guides or instruction sheets.
- Ahead, we’ll explore the surprising connection between TMJ issues and hypothyroidism.
DOSAGE AND ADMINISTRATION
Initiate appropriate supportive treatment as dictated by the patient’s medical status. The recommended daily dosage of SYNTHROID in pregnant patients is described in Table 3. The “optimal dose” was determined for each patient as that dosage of thyroxine being taken when the thyrotropin-releasing hormone (TRH) response was normal (ie, an increase in TSH of between 4.7 and 25 mIU/L). Check with your doctor right away if you have weakness, confusion or non-responsiveness, feeling cold, low body temperature, swelling of the body, especially the face, tongue, and lower legs, or difficulty breathing. These could be symptoms of severe hypothyroidism, called myxedema coma, which may be life-threatening and requires immediate medical attention. Cotton seed meal, dietary fiber, soybean flour (infant formula), or walnuts may decrease the absorption of this medicine from your body.
Drug Interactions for Synthroid
You may have to take this medicine for 4 to 8 weeks before your symptoms start to get better. Using this medicine with any of the following may cause an increased risk of certain side effects but may be unavoidable in some cases. If used together, your doctor may change the dose or how often you use this medicine, or give you special instructions about the use of food, alcohol, or tobacco. Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of levothyroxine in the elderly.
Seizures occurred in a 3-yearold child ingesting 3.6 mg of levothyroxine. Symptoms may not necessarily be evident or may not appear until several days after ingestion of levothyroxine sodium. Because of the increased prevalence of cardiovascular disease among the elderly, initiate SYNTHROID at less than the full replacement dose see DOSAGE AND ADMINISTRATION and WARNINGS AND PRECAUTIONS. Initiate SYNTHROID therapy in this population at lower doses than those recommended in younger individuals or in patients without cardiac disease see DOSAGE AND ADMINISTRATION and Use In Specific Populations. For adult patients with primary hypothyroidism, titrate until the patient is clinically euthyroid and the serum TSH returns to normal see Recommended Dosage And Titration. The signs and symptoms of overdosage are those of hyperthyroidism see Warnings and Precautions (5) and Adverse Reactions (6).
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. A portion of the conjugated hormone reaches the colon unchanged and is eliminated in the feces. Dr. Frieze suggests educating patients on the importance of consistent therapy & precise dosing with Synthroid. In order for Synthroid to be effective, it should always be taken the same way every day. This is important because the amount of medicine you need is very precise.
Thyroid hormones exert their physiologic actions through control of DNA transcription and protein synthesis. Triiodothyronine (T3) and L-thyroxine (T4) diffuse into the cell nucleus and bind to thyroid receptor proteins attached to DNA. This hormone nuclear receptor complex activates gene transcription and synthesis of messenger RNA and cytoplasmic proteins. The physiological actions of thyroid hormones are produced predominantly by T3, the majority of which (approximately 80%) is derived from T4 by deiodination in peripheral tissues. Biotin supplementation is known to interfere with thyroid hormone immunoassays that are based on a biotin and streptavidin interaction, which may result in erroneous thyroid hormone test results.
WARNING: NOT FOR TREATMENT OF OBESITY OR FOR WEIGHT LOSS
If cardiac symptoms develop or worsen, reduce the SYNTHROID dose or withhold for one week and restart at a lower dose. SYNTHROID is contraindicated in patients with uncorrected adrenal insufficiency see Warnings and Precautions (5.4). The peak therapeutic effect of a given dose of SYNTHROID may not be attained for 4 to 6 weeks.
Seizures occurred in a 3-year-old child ingesting 3.6 mg of levothyroxine. Concurrent use of sympathomimetics and SYNTHROID may increase the effects of sympathomimetics or thyroid hormone. Thyroid hormones may increase the risk of coronary insufficiency when sympathomimetic agents are administered to patients with coronary artery disease. Hypersensitivity reactions to inactive ingredients have occurred in patients treated with thyroid hormone products. These include urticaria, pruritus, skin rash, flushing, angioedema, various gastrointestinal symptoms (abdominal pain, nausea, vomiting and diarrhea), fever, arthralgia, serum sickness, and wheezing.
2 Cardiac Adverse Reactions in the Elderly and in Patients with Underlying Cardiovascular Disease
Thyroid hormones are also metabolized via conjugation with glucuronides and sulfates and excreted directly into the bile and gut where they undergo enterohepatic recirculation. 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). Consumption of certain ciprofloxacin synthroid foods may affect SYNTHROID absorption thereby necessitating adjustments in dosing see Dosage and Administration (2.1). Soybean flour, cottonseed meal, walnuts, and dietary fiber may bind and decrease the absorption of SYNTHROID from the gastrointestinal tract.
Atrial fibrillation is the most common of the arrhythmias observed with levothyroxine overtreatment in the elderly. Levothyroxine is generally continued for life in these patients see Warnings and Precautions (5.1). Toxic effects may include increased risk of cardiac arrhythmias and central nervous system stimulation.
