Synthroid Uses, Dosage & Side Effects

Levothyroxine is given when your thyroid does not produce enough of this hormone on its own. The pituitary gland sends out TSH, which tells the thyroid to produce the thyroid hormones thyroxine (T4) and triiodothyronine (T3). Thyroid hormones exert their physiologic actions through control of DNA transcription and protein synthesis. Triiodothyronine (T3) and L-thyroxine (T4) diffuse into the cell synthroid nightmares nucleus and bind to thyroid receptor proteins attached to DNA.

Use In Specific Populations

Seizures occurred in a 3-year-old 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. Consumption of certain 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. Grapefruit juice may delay the absorption of levothyroxine and reduce its bioavailability. Titrate the dose of SYNTHROID carefully and monitor response to titration to avoid these effects see Dosage and Administration (2.4).

Does Synthroid interact with my other drugs?

• Levothyroxine is given when your thyroid does not produce enough of this hormone on its own.
• TSH lower limit of quantification was 0.2 mIU/L and upper limit of normal was 5.6 mIU/L, as indicated by the shaded area.
• Synthroid is prescribed in tablets that range from 25 to 300 mcg in strength and is usually taken once a day with a full glass of water (about 8 ounces) 30 to 60 minutes before breakfast for best adsorption into the body.
• 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.

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 major pathway of thyroid hormone metabolism is through sequential deiodination. Approximately 80% of circulating T3 is derived from peripheral T4 by monodeiodination.

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. And even the way you take Synthroid can affect how much medicine your body is getting. It’s important to always take your medication exactly as your doctor prescribed. Seizures have been reported rarely with the institution of levothyroxine therapy.

If cardiac symptoms develop or worsen, reduce the SYNTHROID dose or withhold for one week and restart at a lower dose. Concurrent use of ketamine and SYNTHROID may produce marked hypertension and tachycardia. Closely monitor blood pressure and heart rate in these patients. SYNTHROID tablets should be protected from light and moisture. The peak therapeutic effect of a given dose of SYNTHROID may not be attained for 4 to 6 weeks. Administer SYNTHROID at least 4 hours before or after drugs known to interfere with SYNTHROID absorption see DRUG INTERACTIONS.

• Synthroid works best if you take it on an empty stomach, 30 to 60 minutes before breakfast.
• Toxic effects may include increased risk of cardiac arrhythmias and central nervous system stimulation.
• Published studies report that levothyroxine is present in human milk following the administration of oral levothyroxine.
• Providing a complete list of medications to the doctor will help with getting the correct dose established for each individual patient.

Thyroid hormone increases metabolic clearance of glucocorticoids. Initiation of thyroid hormone therapy prior to initiating glucocorticoid therapy may precipitate an acute adrenal crisis in patients with adrenal insufficiency. Treat patients with adrenal insufficiency with replacement glucocorticoids prior to initiating treatment with SYNTHROID see Contraindications (4).

Synthroid side effects

Hypothyroidism is when the thyroid gland doesn’t make enough of the thyroid hormone called thyroxine (T4). This causes the body’s system to slow down and can lead to symptoms like fatigue, feeling cold, weight gain due to fluid retention, dry skin, and hair loss. 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). Inquire whether patients are taking biotin or biotin-containing supplements.

Tirosint is used for hashimoto’s disease, hypothyroidism, after thyroid removal, myxedema coma … Your child’s dose needs may change if the child gains or loses weight. Synthroid works best if you take it on an empty stomach, 30 to 60 minutes before breakfast. Follow your doctor’s dosing instructions and try to take the medicine at the same time each day.

If you become pregnant while taking Synthroid, do not stop taking the medicine without your doctor’s advice. Having low thyroid hormone levels during pregnancy could harm both mother and baby. 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). 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. Consumption of certain foods may affect SYNTHROID absorption thereby necessitating adjustments in dosing see DOSAGE AND ADMINISTRATION.

Armour Thyroid

Thyroid hormones may increase the risk of coronary insufficiency when sympathomimetic agents are administered to patients with coronary artery disease. Toxic effects may include increased risk of cardiac arrhythmias and central nervous system stimulation. Administration of sertraline in patients stabilized on SYNTHROID may result in increased SYNTHROID requirements.