Tirosint
levothyroxine sodium · Capsule · Oral
Uses
1 INDICATION AND USAGE TIROSINT-SOL is L-thyroxine (T4) indicated in adult and pediatric patients, including neonates, for: Hypothyroidism - As replacement therapy in primary (thyroidal), secondary (pituitary), and tertiary (hypothalamic) congenital or acquired hypothyroidism ( 1 ) Pituitary Thyrotropin (Thyroid-Stimulating Hormone, TSH) Suppression - As an adjunct to surgery and radioiodine therapy in the management of thyrotropin-dependent well-differentiated thyroid cancer ( 1 ) Limitations of Use Not indicated for suppression of benign thyroid nodules and nontoxic diffuse goiter in iodine-sufficient patients ( 1 ) Not indicated for treatment of transient hypothyroidism during the recovery phase of subacute thyroiditis ( 1 ) Hypothyroidism TIROSINT-SOL is indicated in adult and pediatric patients, including neonates, as a replacement therapy in primary (thyroidal), secondary (pituitary), and tertiary (hypothalamic) congenital or acquired hypothyroidism. Pituitary Thyrotropin (Thyroid-Stimulating Hormone, TSH) Suppression TIROSINT-SOL is indicated in adult and pediatric patients, including neonates, as an adjunct to surgery and radioiodine therapy in the management of thyrotropin-dependent well-differentiated thyroid cancer. Limitations of Use Tirosint-SOL is not indicated for suppression of benign thyroid nodules and nontoxic diffuse goiter in iodine-sufficient patients as there are no clinical benefits and overtreatment with TIROSINT-SOL may induce hyperthyroidism [see Warnings and Precautions (5.1) ] . Tirosint-SOL is not indicated for treatment of transient hypothyroidism during the recovery phase of subacute thyroiditis.
Dosage and administration
Administer once daily, on an empty stomach, 15 minutes before breakfast ( 2.1 ) Administer at least 4 hours before or after drugs that are known to interfere with absorption ( 2.1 ) Evaluate the need for dose adjustments when regularly administering within an hour of certain foods that may affect TIROSINT-SOL absorption ( 2.1 ) To administer TIROSINT-SOL in water, squeeze the contents of one single unit-dose ampule into a glass or cup containing water ( 2.1 ) To administer TIROSINT-SOL directly, either squeeze it into the mouth OR onto a spoon and immediately consume ( 2.1 ) Starting dose depends on a variety of factors, including age, body weight, cardiovascular status, and concomitant medications, co-administered food, and the specific nature of the condition being treated. Peak therapeutic effect may not be attained for 4-6 weeks ( 2.2 ) See full prescribing information for dosing in specific patient populations ( 2.3 ) Adequacy of therapy determined with periodic monitoring of TSH and/or T4 as well as clinical status ( 2.4 ) 2.1 General Administration Information Administer TIROSINT-SOL as a single daily oral dose, on an empty stomach,15 minutes before breakfast. Administer TIROSINT-SOL at least 4 hours before or after drugs known to interfere with TIROSINT-SOL absorption [see Drug Interactions (7.1)] . Evaluate the need for dose adjustments when regularly administering within an hour of certain foods that may affect TIROSINT-SOL absorption [see Dosage and Administration (2.2 and 2.3) , Drug Interactions (7.9) and Clinical Pharmacology (12.3) ] . TIROSINT-SOL may be administered in water or directly into the mouth: To administer TIROSINT-SOL in water, squeeze the contents of one single unit-dose ampule into a glass or cup containing water. Stir the diluted TIROSINT-SOL and drink all of it immediately. Rinse the glass or cup with additional water and drink the contents to ensure that the total dose is taken. Do not dilute TIROSINT-SOL in a medium other than water. Open the ampule and prepare the solution immediately before intake. To administer TIROSINT-SOL directly (without water), either squeeze it into the mouth OR onto a spoon and immediately consume. 2.2 Important Considerations for Dosing The dosage of TIROSINT-SOL for hypothyroidism or pituitary TSH suppression depends on a variety of factors including: the patient's age, body weight, cardiovascular status, concomitant medical conditions (including pregnancy), concomitant medications, co-administered food, and the specific nature of the condition being treated [see Dosage and Administration (2.3), Warnings and Precautions (5), and Drug Interactions (7)] . Dosing must be individualized to account for these factors and dosage adjustments made based on periodic assessment of the patient's clinical response and laboratory parameters [see Dosage and Administration (2.4)] . For adult patients with primary hypothyroidism, titrate until the patient is clinically euthyroid and the serum TSH returns to normal [see Dosage and Administration (2.3)]. For secondary or tertiary hypothyroidism, serum TSH is not a reliable measure of TIROSINT-SOL dosage adequacy and should not be used to monitor therapy. Use the serum free-T4 level to titrate TIROSINT-SOL dosing until the patient is clinically euthyroid and the serum free-T4 level is restored to the upper half of the normal range [see Dosage and Administration (2.3)]. The peak therapeutic effect of a given dose of TIROSINT-SOL may not be attained for 4 to 6 weeks. 2.3 Recommended Dosage and Titration Primary, Secondary, and Tertiary Hypothyroidism in Adults The recommended starting daily dosage of TIROSINT-SOL in adults with primary, secondary, or tertiary hypothyroidism is based on age and comorbid cardiac conditions, as described in Table 1. For patients at risk of atrial fibrillation or patients with underlying cardiac disease, start with a lower dosage and titrate the dosage more slowly to avoid exacerbation of cardiac symptoms. Dosage titration is based on serum TSH or free-T4 [see Dosage and Administration (2.2) ]. Table 1. TIROSINT-SOL Dosing Guidelines for Hypothyroidism in Adults* Patient Population Starting Dosage Dosage Titration Based on Serum TSH or Free-T4 Adults diagnosed with hypothyroidism Full replacement dose is 1.6 mcg/kg/day. Some patients require a lower starting dose. Titrate dosage by 12.5 to 25 mcg increments every 4 to 6 weeks, as needed until the patient is euthyroid. Adults at risk for atrial fibrillation or with underlying cardiac disease Lower starting dose (less than 1.6 mcg/kg/day) Titrate dosage every 6 to 8 weeks, as needed until the patient is euthyroid. Geriatric patients Lower starting dose (less than 1.6 mcg/kg/day) *Dosages greater than 200 mcg/day are seldom required. An inadequate response to daily dosages greater than 300 mcg/day is rare and may indicate poor compliance, malabsorption, drug interactions, or a combination of these factors [see Dosage and Administration (2.1) and Drug Interactions (7) ]. Primary, Secondary, and Tertiary Hypothyroidism in Pediatric Patients The recommended starting daily dosage of TIROSINT-SOL in pediatric patients with primary, secondary, or tertiary hypothyroidism is based on body weight and changes with age as described in Table 2. Titrate the dosage (every 2 weeks) as needed based on serum TSH or free-T4 until the patient is euthyroid [see Dosage and Administration (2.2) ]. Table 2. TIROSINT-SOL Dosing Guidelines for Hypothyroidism in Pediatric Patients Age Starting Daily Dosage Per Kg Body Weight * 0-3 months 10-15 mcg/kg/day 3-6 months 8-10 mcg/kg/day 6-12 months 6-8 mcg/kg/day 1-5 years 5-6 mcg/kg/day 6-12 years 4-5 mcg/kg/day Greater than 12 years but growth and puberty incomplete 2-3 mcg/kg/day Growth and puberty complete 1.6 mcg/kg/day *Adjust dosage based on clinical response and laboratory parameters [see Dosage and Administration (2.4) and Use in Specific Populations (8.4) ].
Dosage forms and strengths
3 DOSAGE FORMS AND STRENGTHS TIROSINT-SOL oral solution is a clear, colorless to slightly yellow solution supplied in a 1 mL white, non-transparent, unit-dose ampule. Each ampule bears a colored label with the dosage strength and the product name (TIROSINT-SOL) (Table 4). Table 4. TIROSINT-SOL Solution Strengths and Identifying Features Strength (mcg/mL) Color 13 Green 25 Orange 37.5 Dark Blue 44 Red 50 White 75 Purple 62.5 Grey 88 Olive 100 Yellow 112 Rose 125 Brown 137 Turquoise 150 Blue 175 Lilac 200 Pink Oral solution: 13, 25, 37.5, 44, 50, 62.5, 75, 88, 100, 112, 125, 137, 150, 175, 200 mcg/mL ( 3 )
Contraindications
4 CONTRAINDICATIONS TIROSINT-SOL is contraindicated in patients with: Hypersensitivity to glycerol, the inactive ingredient in TIROSINT-SOL [see Adverse Events (6) ]. Uncorrected adrenal insufficiency [see Warnings and Precautions (5.4) ] Hypersensitivity to glycerol ( 4 ) Uncorrected adrenal insufficiency ( 4 )
Warnings and precautions
Serious risks related to overtreatment or undertreatment with TIROSINT-SOL: Titrate the dose of TIROSINT-SOL carefully and monitor response to titration. ( 5.1 ) Cardiac adverse reactions in the elderly and in patients with underlying cardiovascular disease : Initiate TIROSINT-SOL at less than the full replacement dose because of the increased risk of cardiac adverse reactions, including atrial fibrillation. ( 2.3 , 5.2 , 8.5 ) Myxedema coma: Do not use oral thyroid hormone drug products to treat myxedema coma. ( 5.3 ) Acute adrenal crisis in patients with concomitant adrenal insufficiency: Treat with replacement glucocorticoids prior to initiation of TIROSINT‑SOL treatment. ( 5.4 ) Worsening of diabetic control: therapy in patients with diabetes mellitus may worsen glycemic control and result in increased antidiabetic agent or insulin requirements. Carefully monitor glycemic control after starting, changing, or discontinuing thyroid hormone therapy. ( 5.5 ) Decreased bone mineral density associated with thyroid hormone over-replacement: Over-replacement can increase bone resorption and decrease bone mineral density. Give the lowest effective dose. 5.6 ) 5.1 Serious Risks Related to Overtreatment or Undertreatment with TIROSINT-SOL TIROSINT-SOL has a narrow therapeutic index. Overtreatment or undertreatment with TIROSINT-SOL may have negative effects on growth and development, cardiovascular function, bone metabolism, reproductive function, cognitive function, gastrointestinal function, and glucose and lipid metabolism in adult or pediatric patients. In pediatric patients with congenital and acquired hypothyroidism, undertreatment may adversely affect cognitive development and linear growth, and overtreatment is associated with craniosynostosis and acceleration of bone age [see Use in Specific Populations (8.4)]. Titrate the dose of TIROSINT-SOL carefully and monitor response to titration to avoid these effects [see Dosage and Administration (2.4)]. Consider the potential for food or drug interactions and adjust the administration or dosage of TIROSINT-SOL as needed [see Dosage and Administration (2.4), Drug Interactions (7.1), and Clinical Pharmacology (12.3)]. 5.2 Cardiac Adverse Reactions in the Elderly and in Patients with Underlying Cardiovascular Disease Overtreatment with levothyroxine may cause an increase in heart rate, cardiac wall thickness, and cardiac contractility, and may precipitate angina or arrhythmias, particularly in patients with cardiovascular disease and in elderly patients. Initiate TIROSINT-SOL therapy in this population at lower doses than those recommended in younger individuals or in patients without cardiac disease [see Dosage and Administration (2.3) and Use in Specific Populations (8.5) ]. Monitor for cardiac arrhythmias during surgical procedures in patients with coronary artery disease receiving suppressive TIROSINT-SOL therapy. Monitor patients receiving concomitant TIROSINT-SOL and sympathomimetic agents for signs and symptoms of coronary insufficiency . If cardiac symptoms develop or worsen, reduce the TIROSINT-SOL dose or withhold it for one week and restart at a lower dose. 5.3 Myxedema Coma Myxedema coma is a life-threatening emergency characterized by poor circulation and hypometabolism, and may result in unpredictable absorption of levothyroxine sodium from the gastrointestinal tract. Use of oral thyroid hormone drug products is not recommended to treat myxedema coma. Administer thyroid hormone products formulated for intravenous administration to treat myxedema coma. 5.4 Acute Adrenal Crisis in Patients with Concomitant Adrenal Insufficiency 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 TIROSINT-SOL [see Contraindications (4)]. 5.5 Worsening of Diabetic Control Addition of levothyroxine therapy in patients with diabetes mellitus may worsen glycemic control and result in increased antidiabetic agent or insulin requirements. Carefully monitor glycemic control after starting, changing, or discontinuing TIROSINT-SOL [see Drug Interactions (7.2) ] . 5.6 Decreased Bone Mineral Density Associated with Thyroid Hormone Over-Replacement Increased bone resorption and decreased bone mineral density may occur as a result of levothyroxine over-replacement, particularly in post-menopausal women. The increased bone resorption may be associated with increased serum levels and urinary excretion of calcium and phosphorous, elevations in bone alkaline phosphatase, and suppressed serum parathyroid hormone levels. Administer the minimum dose of TIROSINT-SOL that achieves the desired clinical and biochemical response to mitigate this risk.
Side effects
Adverse reactions associated with TIROSINT-SOL therapy are primarily those of hyperthyroidism due to therapeutic overdosage [see Warnings and Precautions (5) and Overdosage (10) ]. They include the following: General: fatigue, increased appetite, weight loss, heat intolerance, fever, excessive sweating Central nervous system: headache, hyperactivity, nervousness, anxiety, irritability, emotional lability, insomnia Musculoskeletal: tremors, muscle weakness, muscle spasm Cardiovascular: palpitations, tachycardia, arrhythmias, increased pulse and blood pressure, heart failure, angina, myocardial infarction, cardiac arrest Respiratory : dyspnea Gastrointestinal (GI): diarrhea, vomiting, abdominal cramps, elevations in liver function tests Dermatologic: hair loss, flushing, rash Endocrine: decreased bone mineral density Reproductive: menstrual irregularities, impaired fertility Seizures have been reported rarely with the institution of levothyroxine therapy. Adverse reactions associated with TIROSINT-SOL are primarily those of hyperthyroidism due to therapeutic overdosage including: arrhythmias, myocardial infarction, dyspnea, muscle spasm, headache, nervousness, irritability, insomnia, tremors, muscle weakness, increased appetite, weight loss, diarrhea, heat intolerance, menstrual irregularities, and skin rash ( 6 ) To report SUSPECTED ADVERSE REACTIONS, contact IBSA Pharma Inc. at 1-800-587-3513, or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . Adverse Reactions in Pediatric Patients Pseudotumor cerebri and slipped capital femoral epiphysis have been reported in pediatric patients receiving levothyroxine therapy. Overtreatment may result in craniosynostosis in infants who have not undergone closure of the fontanelles, and in premature closure of the epiphyses in pediatric patients still experiencing growth with resultant compromised adult height. Hypersensitivity Reactions Hypersensitivity reactions to inactive ingredients have occurred in patients treated with thyroid hormone products. These include urticaria, pruritus, skin rash, flushing, angioedema, various GI symptoms (abdominal pain, nausea, vomiting and diarrhea), fever, arthralgia, serum sickness, and wheezing. Hypersensitivity to levothyroxine itself is not known to occur.
Drug interactions
See full prescribing information for drugs that affect thyroid hormone pharmacokinetics and metabolism (e.g., absorption, synthesis, secretion, catabolism, protein binding, and target tissue response) and may alter the therapeutic response to TIROSINT-SOL ( 7 ) 7.1 Drugs Known to Affect Thyroid Hormone Pharmacokinetics Many drugs can exert effects on thyroid hormone pharmacokinetics and metabolism (e.g., absorption, synthesis, secretion, catabolism, protein binding, and target tissue response) and may alter the therapeutic response to TIROSINT-SOL (Tables 5 to 8). Table 5. Drugs That May Decrease T4 Absorption (Hypothyroidism) Potential impact: Concurrent use may reduce the efficacy of TIROSINT-SOL by binding and delaying or preventing absorption, potentially resulting in hypothyroidism. Drug or Drug Class Effect Phosphate Binders (e.g., calcium carbonate, ferrous sulfate, sevelamer, lanthanum) Phosphate binders may bind to levothyroxine. Administer TIROSINT-SOL at least 4 hours apart from these agents. Orlistat Monitor patients treated concomitantly with orlistat and TIROSINT‑SOL for changes in thyroid function. Bile Acid Sequestrants (e.g., colesevelam, cholestyramine, colestipol Ion Exchange Resins (e.g., Kayexalate) Bile acid sequestrants and ion exchange resins are known to decrease levothyroxine absorption. Administer TIROSINT-SOL at least 4 hours prior to these drugs or monitor TSH levels. Sucralfate Antacids (e.g., aluminum & magnesium hydroxides, simethicone) Gastric acidity is an essential requirement for adequate absorption of levothyroxine. However, gastric acidity may not be as essential for the absorption of TIROSINT-SOL. Sucralfate and antacids may cause hypochlorhydria, affect gastric pH, and reduce levothyroxine absorption. Monitor patients appropriately. Table 6. Drugs That May Alter T4 and Triiodothyronine (T3) Serum Transport Without Affecting Free Thyroxine (FT4) Concentration (Euthyroidism) Drug or Drug Class Effect Clofibrate Estrogen-containing oral contraceptives Estrogens (oral) Heroin / Methadone 5-Fluorouracil Mitotane Tamoxifen These drugs may increase serum thyroxine-binding globulin (TBG) concentration. Androgens / Anabolic Steroids Asparaginase Glucocorticoids Slow-Release Nicotinic Acid These drugs may decrease serum TBG concentration. Potential impact (below): Administration of these agents with TIROSINT-SOL results in an initial transient increase in FT4. Continued administration results in a decrease in serum T4 and normal FT4 and TSH concentrations. Salicylates (> 2 g/day) Salicylates inhibit binding of T4 and T3 to TBG and transthyretin. An initial increase in serum FT4 is followed by return of FT4 to normal levels with sustained therapeutic serum salicylate concentrations, although total T4 levels may decrease by as much as 30%. Other drugs: Carbamazepine Furosemide (> 80 mg IV) Heparin Hydantoins Non-Steroidal Anti-inflammatory Drugs: Fenamates These drugs may cause protein-binding site displacement. Furosemide has been shown to inhibit the protein binding of T4 to TBG and albumin, causing an increase free‑T4 fraction in serum. Furosemide competes for T4-binding sites on TBG, prealbumin, and albumin, so that a single high dose can acutely lower the total T4 level. Phenytoin and carbamazepine reduce serum protein binding of levothyroxine, and total and free‑T4 may be reduced by 20% to 40%, but most patients have normal serum TSH levels and are clinically euthyroid. Closely monitor thyroid hormone parameters. Table 7. Drugs That May Alter Hepatic Metabolism of T4 (Hypothyroidism) Potential impact: Stimulation of hepatic microsomal drug-metabolizing enzyme activity may cause increased hepatic degradation of levothyroxine, resulting in increased TIROSINT-SOL requirements. Drug or Drug Class Effect Phenobarbital Rifampin Phenobarbital has been shown to reduce the response to thyroxine. Phenobarbital increases L-thyroxine metabolism by inducing uridine 5’ diphospho-glucuronosyltransferase (UGT) and leads to a lower T4 serum levels. Changes in thyroid status may occur if barbiturates are added or withdrawn from patients being treated for hypothyroidism. Rifampin has been shown to accelerate the metabolism of levothyroxine. Table 8. Drugs That May Decrease Conversion of T4 to T3 Potential impact: Administration of these enzyme inhibitors decreases the peripheral conversion of T4 to T3, leading to decreased T3 levels. However, serum T4 levels are usually normal but may occasionally be slightly increased. Drug or Drug Class Effect Beta-adrenergic antagonists (e.g., Propranolol > 160 mg/day) In patients treated with large doses of propranolol (> 160 mg/day), T3 and T4 levels change, TSH levels remain normal, and patients are clinically euthyroid. Actions of particular beta-adrenergic antagonists may be impaired when a hypothyroid patient is converted to the euthyroid state. Glucocorticoids (e.g., Dexamethasone > 4 mg/day) Short-term administration of large doses of glucocorticoids may decrease serum T3 concentrations by 30% with minimal change in serum T4 levels. However, long-term glucocorticoid therapy may result in slightly decreased T3 and T4 levels due to decreased TBG production (See above). Other drugs: Amiodarone Amiodarone inhibits peripheral conversion of T4 to T3 and may cause isolated biochemical changes (increase in serum free-T4, and decrease or normal free-T3) in clinically euthyroid patients. 7.2 Antidiabetic Therapy Addition of TIROSINT-SOL therapy in patients with diabetes mellitus may worsen glycemic control and result in increased antidiabetic agent or insulin requirements. Carefully monitor glycemic control, especially when thyroid therapy is started, changed, or discontinued [see Warnings and Precautions (5.5) ] . 7.3 Oral Anticoagulants TIROSINT-SOL increases the response to oral anticoagulant therapy.
Use in specific populations
Pregnancy may require the use of higher doses of TIROSINT-SOL ( 2.3 , 8.1 ) See 17 for PATIENT COUNSELING INFORMATION and FDA‑approved patient labeling. 8.1 Pregnancy Risk Summary The clinical experience, including data from published postmarketing studies, in pregnant women treated with oral levothyroxine to maintain euthyroid state have not reported increased rates of major birth defects, miscarriages, or other adverse maternal or fetal outcomes. There are risks to the mother and fetus associated with untreated hypothyroidism in pregnancy. Since TSH levels may increase during pregnancy, TSH should be monitored and TIROSINT‑SOL dosage adjusted during pregnancy [see Clinical Considerations ] . Animal reproductive studies have not been conducted with levothyroxine sodium. TIROSINT-SOL should not be discontinued during pregnancy and hypothyroidism diagnosed during pregnancy should be promptly treated. The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively. Clinical Considerations Disease-Associated Maternal and/or Embryo/Fetal Risk Maternal hypothyroidism during pregnancy is associated with a higher rate of complications, including spontaneous abortion, gestational hypertension, pre-eclampsia, stillbirth, and premature delivery. Untreated maternal hypothyroidism may have an adverse effect on fetal neurocognitive development. Dose Adjustments During Pregnancy and the Postpartum Period Pregnancy may increase TIROSINT-SOL requirements. Serum TSH levels should be monitored and the TIROSINT-SOL dosage adjusted during pregnancy. Since postpartum TSH levels are similar to preconception values, the TIROSINT-SOL dosage should return to the pre-pregnancy dose immediately after delivery [see Dosage and Administration (2.3) ]. 8.2 Lactation Risk Summary Published studies report that levothyroxine is present in human milk following the administration of oral levothyroxine. No adverse effects on the breastfed infant have been reported and this no information on the effects of levothyroxine on milk production. Adequate levothyroxine treatment during lactation may normalize milk production in hypothyroid lactating mothers with low milk supply. The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for TIROSINT-SOL and any potential adverse effects on the breastfed infant from TIROSINT-SOL or from the underlying maternal condition. 8.4 Pediatric Use TIROSINT-SOL is indicated in patients from birth to less than 17 years of age: As a replacement therapy in primary (thyroidal), secondary (pituitary), and tertiary (hypothalamic) congenital or acquired hypothyroidism As an adjunct to surgery and radioiodine therapy in the management of thyrotropin-dependent well-differentiated thyroid cancer 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. Therefore, initiate TIROSINT-SOL therapy immediately upon diagnosis. Levothyroxine is generally continued for life in these patients [see Warnings and Precautions (5.1) ]. Closely monitor infants during the first two weeks of TIROSINT-SOL therapy for cardiac overload and arrhythmias. 8.5 Geriatric Use Because of the increased prevalence of cardiovascular disease among the elderly, initiate TIROSINT-SOL at less than the full replacement dose [ see Dosage and Administration (2.3) and Warnings and Precautions (5.1) ]. Atrial arrhythmias can occur in elderly patients. Atrial fibrillation is the most common of the arrhythmias observed with levothyroxine overtreatment in the elderly .
Pregnancy
8.1 Pregnancy Risk Summary The clinical experience, including data from published postmarketing studies, in pregnant women treated with oral levothyroxine to maintain euthyroid state have not reported increased rates of major birth defects, miscarriages, or other adverse maternal or fetal outcomes. There are risks to the mother and fetus associated with untreated hypothyroidism in pregnancy. Since TSH levels may increase during pregnancy, TSH should be monitored and TIROSINT‑SOL dosage adjusted during pregnancy [see Clinical Considerations ] . Animal reproductive studies have not been conducted with levothyroxine sodium. TIROSINT-SOL should not be discontinued during pregnancy and hypothyroidism diagnosed during pregnancy should be promptly treated. The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively. Clinical Considerations Disease-Associated Maternal and/or Embryo/Fetal Risk Maternal hypothyroidism during pregnancy is associated with a higher rate of complications, including spontaneous abortion, gestational hypertension, pre-eclampsia, stillbirth, and premature delivery. Untreated maternal hypothyroidism may have an adverse effect on fetal neurocognitive development. Dose Adjustments During Pregnancy and the Postpartum Period Pregnancy may increase TIROSINT-SOL requirements. Serum TSH levels should be monitored and the TIROSINT-SOL dosage adjusted during pregnancy. Since postpartum TSH levels are similar to preconception values, the TIROSINT-SOL dosage should return to the pre-pregnancy dose immediately after delivery [see Dosage and Administration (2.3) ].
Pediatric use
8.4 Pediatric Use TIROSINT-SOL is indicated in patients from birth to less than 17 years of age: As a replacement therapy in primary (thyroidal), secondary (pituitary), and tertiary (hypothalamic) congenital or acquired hypothyroidism As an adjunct to surgery and radioiodine therapy in the management of thyrotropin-dependent well-differentiated thyroid cancer 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. Therefore, initiate TIROSINT-SOL therapy immediately upon diagnosis. Levothyroxine is generally continued for life in these patients [see Warnings and Precautions (5.1) ]. Closely monitor infants during the first two weeks of TIROSINT-SOL therapy for cardiac overload and arrhythmias.
Geriatric use
8.5 Geriatric Use Because of the increased prevalence of cardiovascular disease among the elderly, initiate TIROSINT-SOL at less than the full replacement dose [ see Dosage and Administration (2.3) and Warnings and Precautions (5.1) ]. Atrial arrhythmias can occur in elderly patients. Atrial fibrillation is the most common of the arrhythmias observed with levothyroxine overtreatment in the elderly .
Overdosage
The signs and symptoms of overdosage are those of hyperthyroidism [see Warnings and Precautions (5) and Adverse Reactions (6) ]. In addition, confusion and disorientation may occur. Cerebral embolism, shock, coma, and death have been reported. 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. Reduce the TIROSINT-SOL dose or discontinue temporarily if signs or symptoms of overdosage occur. Initiate appropriate supportive treatment as dictated by the patient's medical status. For current information on the management of poisoning or overdosage, contact the National Poison Control Center at 1-800-222-1222 or www.poison.org.
Description
(levothyroxine sodium) oral solution contains synthetic L-3,3',5,5'-tetraiodothyronine sodium salt [levothyroxine (T4) sodium]. Synthetic T4 is chemically identical to that produced in the human thyroid gland. Levothyroxine (T4) sodium has an empirical formula of C 15 H 10 I 4 NNaO 4 ∙ x H 2 O (where x = 5), molecular weight of 798.86 g/mol (anhydrous), and structural formula as shown: TIROSINT-SOL oral solution is a clear, colorless to slightly yellow solution supplied in a 1 mL white, non-transparent, unit-dose ampule and is available in the following strengths (mcg/mL): 13, 25, 37.5, 44, 50, 62.5, 75, 88, 100, 112, 125, 137, 150, 175, 200. The inactive ingredients in TIROSINT-SOL are glycerol and water. Chemical Structure
Mechanism of action
12.1 Mechanism of Action 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.
How supplied
How Supplied TIROSINT-SOL (levothyroxine sodium) oral solution is a clear, colorless to slightly yellow solution supplied in a 1 mL white, non-transparent, unit-dose ampule. The dosage strength is identified on the box and the pouch, and is associated with a distinct color. Each ampule bears a colored label with the dosage strength and the product name (TIROSINT-SOL) (Table 10). Table 10. TIROSINT-SOL Solution Strengths and Packaging Description Strength (mcg/mL) Color a Box NDC (30 Unit-Dose Ampules) Pouch NDC (5 Unit-Dose Ampules) 13 Green 71858-0105-5 71858-0105-4 25 Orange 71858-0110-5 71858-0110-4 37.5 Dark Blue 71858-0112-5 71858-0112-4 44 Red 71858-0113-5 71858-0113-4 50 White 71858-0115-5 71858-0115-4 62.5 Grey 71858-0117-5 71858-0117-4 75 Purple 71858-0120-5 71858-0120-4 88 Olive 71858-0125-5 71858-0125-4 100 Yellow 71858-0130-5 71858-0130-4 112 Rose 71858-0135-5 71858-0135-4 125 Brown 71858-0140-5 71858-0140-4 137 Turquoise 71858-0145-5 71858-0145-4 150 Blue 71858-0150-5 71858-0150-4 175 Lilac 71858-0155-5 71858-0155-4 200 Pink 71858-0160-5 71858-0160-4 Storage and Handling Store TIROSINT-SOL in the original container (closed pouch) at 20°C to 25°C (68°F to 77°F); excursions permitted to 15° to 30°C (59°F to 86°F) [See USP Controlled Room Temperature]. Use TIROSINT-SOL oral solution within three (3) months after opening the pouch. Keep the ampules in the pouch until ready to use as important information may be lost (i.e., manufacturer/distributor names and distributor contact phone number).
Storage
How Supplied TIROSINT-SOL (levothyroxine sodium) oral solution is a clear, colorless to slightly yellow solution supplied in a 1 mL white, non-transparent, unit-dose ampule. The dosage strength is identified on the box and the pouch, and is associated with a distinct color. Each ampule bears a colored label with the dosage strength and the product name (TIROSINT-SOL) (Table 10). Table 10. TIROSINT-SOL Solution Strengths and Packaging Description Strength (mcg/mL) Color a Box NDC (30 Unit-Dose Ampules) Pouch NDC (5 Unit-Dose Ampules) 13 Green 71858-0105-5 71858-0105-4 25 Orange 71858-0110-5 71858-0110-4 37.5 Dark Blue 71858-0112-5 71858-0112-4 44 Red 71858-0113-5 71858-0113-4 50 White 71858-0115-5 71858-0115-4 62.5 Grey 71858-0117-5 71858-0117-4 75 Purple 71858-0120-5 71858-0120-4 88 Olive 71858-0125-5 71858-0125-4 100 Yellow 71858-0130-5 71858-0130-4 112 Rose 71858-0135-5 71858-0135-4 125 Brown 71858-0140-5 71858-0140-4 137 Turquoise 71858-0145-5 71858-0145-4 150 Blue 71858-0150-5 71858-0150-4 175 Lilac 71858-0155-5 71858-0155-4 200 Pink 71858-0160-5 71858-0160-4
Patient information
Advise the patient and/or caregiver to read the FDA-approved patient labeling (Patient Information and Instructions for Use). Dosing and Administration Instruct patients to take TIROSINT-SOL only as directed by their healthcare provider. Instruct patients to take TIROSINT-SOL 15 minutes before breakfast. Instruct patients about the TIROSINT-SOL dosing instructions. Inform patients that agents such as iron and calcium supplements and antacids can decrease the absorption of levothyroxine. Instruct patients not to take TIROSINT-SOL within 4 hours of these agents. Instruct patients to notify their healthcare provider should they become pregnant or are thinking of becoming pregnant while taking TIROSINT-SOL. Important Information Inform patients that it may take several weeks before they notice an improvement in symptoms. Inform patients that the levothyroxine in TIROSINT-SOL is intended to replace a hormone that is normally produced by the thyroid gland. Generally, replacement therapy is to be taken for life. Inform patients that TIROSINT-SOL should not be used as a primary or adjunctive therapy in a weight control program. Instruct patients to notify their healthcare provider if they are taking any other medications, including prescription and over-the-counter preparations. Instruct patients to notify their healthcare provider of any other medical conditions, particularly heart disease, diabetes, clotting disorders, and adrenal or pituitary gland problems, as the dose of medications used to control these other conditions may need to be adjusted while taking TIROSINT-SOL. If they have diabetes, instruct patients to monitor their blood and/or urinary glucose levels as directed by their physician and immediately report any changes to their physician. If patients are taking anticoagulants, their clotting status should be checked frequently. Instruct patients to notify their physician or dentist that they are taking TIROSINT-SOL prior to any surgery. Adverse Reactions Instruct patients to notify their healthcare provider if they experience any of the following symptoms: rapid or irregular heartbeat, chest pain, shortness of breath, leg cramps, headache, nervousness, irritability, sleeplessness, tremors, change in appetite, weight loss, vomiting, diarrhea, excessive sweating, heat intolerance, fever, changes in menstrual periods, hives or skin rash, or any other unusual medical event. Inform patients that partial hair loss may occur rarely during the first few months of TIROSINT-SOL therapy, but this is usually temporary.
Label text from the FDA structured product label by IBSA Pharma Inc. (revised Mar 27, 2026). Long sections are shortened; the complete label is on DailyMed.
Active ingredients
- Levothyroxine Sodium in 30 products
Tirosint NDC products (30)
| NDC | Strength & form | Labeler | Type |
|---|---|---|---|
| 71858-0105 | Levothyroxine Sodium 13 ug/mL Solution | IBSA Pharma Inc. | NDA |
| 71858-0160 | Levothyroxine Sodium 200 ug/mL Solution | IBSA Pharma Inc. | NDA |
| 71858-0155 | Levothyroxine Sodium 175 ug/mL Solution | IBSA Pharma Inc. | NDA |
| 71858-0150 | Levothyroxine Sodium 150 ug/mL Solution | IBSA Pharma Inc. | NDA |
| 71858-0145 | Levothyroxine Sodium 137 ug/mL Solution | IBSA Pharma Inc. | NDA |
| 71858-0140 | Levothyroxine Sodium 125 ug/mL Solution | IBSA Pharma Inc. | NDA |
| 71858-0135 | Levothyroxine Sodium 112 ug/mL Solution | IBSA Pharma Inc. | NDA |
| 71858-0130 | Levothyroxine Sodium 100 ug/mL Solution | IBSA Pharma Inc. | NDA |
| 71858-0125 | Levothyroxine Sodium 88 ug/mL Solution | IBSA Pharma Inc. | NDA |
| 71858-0120 | Levothyroxine Sodium 75 ug/mL Solution | IBSA Pharma Inc. | NDA |
| 71858-0117 | Levothyroxine Sodium 62.5 ug/mL Solution | IBSA Pharma Inc. | NDA |
| 71858-0115 | Levothyroxine Sodium 50 ug/mL Solution | IBSA Pharma Inc. | NDA |
| 71858-0113 | Levothyroxine Sodium 44 ug/mL Solution | IBSA Pharma Inc. | NDA |
| 71858-0112 | Levothyroxine Sodium 37.5 ug/mL Solution | IBSA Pharma Inc. | NDA |
| 71858-0110 | Levothyroxine Sodium 25 ug/mL Solution | IBSA Pharma Inc. | NDA |
| 71858-0005 | Levothyroxine Sodium 13 ug/1 Capsule | IBSA Pharma Inc. | NDA |
| 71858-0060 | Levothyroxine Sodium 200 ug/1 Capsule | IBSA Pharma Inc. | NDA |
| 71858-0055 | Levothyroxine Sodium 175 ug/1 Capsule | IBSA Pharma Inc. | NDA |
| 71858-0050 | Levothyroxine Sodium 150 ug/1 Capsule | IBSA Pharma Inc. | NDA |
| 71858-0045 | Levothyroxine Sodium 137 ug/1 Capsule | IBSA Pharma Inc. | NDA |
| 71858-0040 | Levothyroxine Sodium 125 ug/1 Capsule | IBSA Pharma Inc. | NDA |
| 71858-0035 | Levothyroxine Sodium 112 ug/1 Capsule | IBSA Pharma Inc. | NDA |
| 71858-0030 | Levothyroxine Sodium 100 ug/1 Capsule | IBSA Pharma Inc. | NDA |
| 71858-0025 | Levothyroxine Sodium 88 ug/1 Capsule | IBSA Pharma Inc. | NDA |
| 71858-0020 | Levothyroxine Sodium 75 ug/1 Capsule | IBSA Pharma Inc. | NDA |
| 71858-0017 | Levothyroxine Sodium 62.5 ug/1 Capsule | IBSA Pharma Inc. | NDA |
| 71858-0015 | Levothyroxine Sodium 50 ug/1 Capsule | IBSA Pharma Inc. | NDA |
| 71858-0013 | Levothyroxine Sodium 44 ug/1 Capsule | IBSA Pharma Inc. | NDA |
| 71858-0012 | Levothyroxine Sodium 37.5 ug/1 Capsule | IBSA Pharma Inc. | NDA |
| 71858-0010 | Levothyroxine Sodium 25 ug/1 Capsule | IBSA Pharma Inc. | NDA |
Tirosint recalls
- D-0331-2023 Mar 1, 2023 · Class II · Terminated
Subpotent Drug - D-0332-2023 Mar 1, 2023 · Class II · Terminated
Subpotent Drug - D-0333-2023 Mar 1, 2023 · Class II · Terminated
Subpotent Drug - D-0334-2023 Mar 1, 2023 · Class II · Terminated
Subpotent Drug - D-0335-2023 Mar 1, 2023 · Class II · Terminated
Subpotent Drug - D-0336-2023 Mar 1, 2023 · Class II · Terminated
Subpotent Drug - D-0337-2023 Mar 1, 2023 · Class II · Terminated
Subpotent Drug - D-0338-2023 Mar 1, 2023 · Class II · Terminated
Subpotent Drug - D-0339-2023 Mar 1, 2023 · Class II · Terminated
Subpotent Drug - D-0340-2023 Mar 1, 2023 · Class II · Terminated
Subpotent Drug - D-0341-2023 Mar 1, 2023 · Class II · Terminated
Subpotent Drug - D-0342-2023 Mar 1, 2023 · Class II · Terminated
Subpotent Drug - D-0343-2023 Mar 1, 2023 · Class II · Terminated
Subpotent Drug - D-0344-2023 Mar 1, 2023 · Class II · Terminated
Subpotent Drug - D-0345-2023 Mar 1, 2023 · Class II · Terminated
Subpotent Drug - D-0495-2021 Jun 2, 2021 · Class II · Terminated
CGMP Deviations: Intermittent exposure to temperature excursion during storage.
Frequently asked questions
What is Tirosint used for?
1 INDICATION AND USAGE TIROSINT-SOL is L-thyroxine (T4) indicated in adult and pediatric patients, including neonates, for: Hypothyroidism - As replacement therapy in primary (thyroidal), secondary (pituitary), and tertiary (hypothalamic) congenital or acquired hypothyroidism ( 1 ) Pituitary Thyrotropin (Thyroid-Stimulating Hormone, TSH) Suppression - As an adjunct to surgery and radioiodine…
What are the side effects of Tirosint?
Adverse reactions associated with TIROSINT-SOL therapy are primarily those of hyperthyroidism due to therapeutic overdosage [see Warnings and Precautions (5) and Overdosage (10) ]. They include the following: General: fatigue, increased appetite, weight loss, heat intolerance, fever, excessive sweating Central nervous system: headache, hyperactivity, nervousness, anxiety, irritability, emotional… See the full label for the complete list.
Who makes Tirosint?
Tirosint is listed by 1 labeler in the FDA NDC directory, including IBSA Pharma Inc..
Has Tirosint been recalled?
The FDA enforcement database lists 16 recalls for Tirosint, most recently D-0331-2023 (class ii): Subpotent Drug