Levothyroxine sodium 75microgram tablets
Prescription only
Requires a prescription from a doctor or prescriber
Tablet
Oral
Thyroid and antithyroid drugs
Active ingredients:
Levothyroxine
No active safety alerts
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Source: MHRA Products DatabaseOGL 3.0
Updated 3 months ago(16 Jan 2026)Safety monitoring data
Yellow Card reports
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8 branded products available
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Vencamil 75microgram tablets
Levothyroxine sodium 75microgram tablets
Levothyroxine sodium 75microgram tablets
Levothyroxine sodium 75microgram tablets
Levothyroxine sodium 75microgram tablets
Levothyroxine sodium 75microgram tablets
Levothyroxine sodium 75microgram tablets
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£1.94indicative price
This is the NHS Drug Tariff indicative price used for reimbursement purposes. It may not reflect the price paid by patients or pharmacies.
View full Drug TariffSource: NHS Drug Tariff via NHSBSA. Derived from dm+d VMPP (Virtual Medicinal Product Pack) pricing data. Contains public sector information licensed under the Open Government Licence v3.0.
WHO defined daily dose (DDD)
150 microgram
Not a recommended dose. The DDD is the assumed average maintenance dose per day for a drug used for its main indication in adults. It is a statistical measure used for research and comparison purposes only.
Source: WHO Collaborating Centre for Drug Statistics Methodology, distributed via NHS dm+d BNF mapping files. Contains public sector information licensed under the Open Government Licence v3.0.
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Similarity based on WHO Anatomical Therapeutic Chemical (ATC) classification and NHS BNF section grouping. Source data: NHS dm+d via TRUD (OGL v3.0), WHO ATC/DDD Index.
NHS prescribing volume and spending trends
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Clinical guidelines and formulary information
British National Formulary
Levothyroxine
BNF
Drug monograph — bnf.nice.org.ukSource: British National Formulary, NICE. Joint Formulary Committee. Contains public sector information licensed under the Open Government Licence v3.0.
NICE clinical guidance(2)
Thyroid disease: assessment and management (NG145)
NG145
NICE guideline
Updated Oct 2023Ultrasound-guided percutaneous radiofrequency ablation for benign thyroid nodules (HTG416)
HTG416
Guidance
Updated Jun 2016Source: National Institute for Health and Care Excellence (NICE). Contains public sector information licensed under the Open Government Licence v3.0.
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Codes for healthcare professionals and prescribing systems
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SNOMED CT and dm+d codes from NHS TRUD (Technology Reference data Update Distribution), licensed under the Open Government Licence v3.0. BNF codes from NHS Business Services Authority (NHSBSA). ATC codes from the WHO Collaborating Centre for Drug Statistics Methodology (whocc.no).
Active and completed clinical studies from ClinicalTrials.gov
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Source: ClinicalTrials.gov, a database of the U.S. National Library of Medicine (NLM), National Institutes of Health (NIH). Data accessed via ClinicalTrials.gov API v2. Trial information is provided for research purposes and does not constitute medical advice.
Pharmacology and chemical data from DrugBank
Key facts
Drug status
Approved
Major interactions
None known
Half-life
6 to 7 days
Mechanism
Levothyroxine is a synthetically prepared levo-isomer of the thyroid hormone thy…
Food interactions
6 warnings
Human targets
4 targets
Data: DrugBank · CC BY-NC 4.0
Pharmacokinetics at a glance
Absorption
40%
Absorption of orally administered T4 from the gastrointestinal tract ranges from 40% to 80% with the majority of the levothyroxine dose absorbed from the jejunum and upper ileum.…
Half-life
6 to 7 days
T4 half-life is 6 to 7 days. T3 half-life is 1 to 2 days.F4636
Protein binding
99%
Circulating thyroid hormones are greater than 99% bound to plasma proteins, including thyroxine-binding globulin (TBG), thyroxine-binding prealbumin (TBPA) and albumin (TBA).…
Metabolism
70%
Approximately 70% of secreted T4 is deiodinated to equal amounts of T3 and reverse triiodothyronine (rT3), which is calorigenically inactive.…
Elimination
20%
Thyroid hormones are primarily eliminated by the kidneys. A portion of the conjugated hormone reaches the colon unchanged and is eliminated in the feces.…
Pharmacokinetic data: DrugBank · CC BY-NC 4.0
Status:
Approved
Investigational
Small molecule
About this compound
Levothyroxine is a synthetically produced form of thyroxine, a major endogenous hormone secreted by the thyroid gland.F4633 Also known as L-thyroxine or the brand name product Synthroid, levothyroxine is used primarily to treat hypothyroidism, a condition where the thyroid gland is no longer able to produce sufficient quantities of the thyroid hormones T4 (tetraiodothyronine or thyroxine) and T3 (triiodothyronine or DB00279), resulting in diminished down-stream effects of these hormones. Without sufficient quantities of circulating thyroid hormones, symptoms of hypothyroidism begin to develop such as fatigue, increased heart rate, depression[A179620], dry skin and hair, muscle cramps, constipation, weight gain, memory impairment, and poor tolerance to cold temperatures.[F4636,A35722]
In response to Thyroid Stimulating Hormone (TSH) release by the pituitary gland, a normally functioning thyroid gland will produce and secrete T4, which is then converted through deiodination (by type I or type II 5′-deiodinases)[A179941] into its active metabolite T3. While T4 is the major product secreted by the thyroid gland, T3 exerts the majority of the physiological effects of the thyroid hormones; T4 and T3 have a relative potency of ~1:4 (T4:T3).F4633 T4 and T3 act on nearly every cell of the body, but have a particularly strong effect on the cardiac system.[A179935] As a result, many cardiac functions including heart rate, cardiac output, and systemic vascular resistance are closely linked to thyroid status.[A179938]
Prior to the development of levothyroxine, DB09100 or desiccated thyroid, used to be the mainstay of treatment for hypothyroidism. However, this is no longer recommended for the majority of patients due to several clinical concerns including limited controlled trials supporting its use. Desiccated thyroid products contain a ratio of T4 to T3 of 4.2:1, which is significantly lower than the 14:1 ratio of secretion by the human thyroid gland. This higher proportion of T3 in desiccated thyroid products can lead to supraphysiologic levels of T3 which may put patients at risk of thyrotoxicosis if thyroid extract therapy is not adjusted according to the serum TSH.[A35722, F4636]
In response to Thyroid Stimulating Hormone (TSH) release by the pituitary gland, a normally functioning thyroid gland will produce and secrete T4, which is then converted through deiodination (by type I or type II 5′-deiodinases)[A179941] into its active metabolite T3. While T4 is the major product secreted by the thyroid gland, T3 exerts the majority of the physiological effects of the thyroid hormones; T4 and T3 have a relative potency of ~1:4 (T4:T3).F4633 T4 and T3 act on nearly every cell of the body, but have a particularly strong effect on the cardiac system.[A179935] As a result, many cardiac functions including heart rate, cardiac output, and systemic vascular resistance are closely linked to thyroid status.[A179938]
Prior to the development of levothyroxine, DB09100 or desiccated thyroid, used to be the mainstay of treatment for hypothyroidism. However, this is no longer recommended for the majority of patients due to several clinical concerns including limited controlled trials supporting its use. Desiccated thyroid products contain a ratio of T4 to T3 of 4.2:1, which is significantly lower than the 14:1 ratio of secretion by the human thyroid gland. This higher proportion of T3 in desiccated thyroid products can lead to supraphysiologic levels of T3 which may put patients at risk of thyrotoxicosis if thyroid extract therapy is not adjusted according to the serum TSH.[A35722, F4636]
Properties:
solid
Avg. mass: 776.87 Da
DrugBank indication
Levothyroxine is indicated as replacement therapy in primary (thyroidal), secondary (pituitary) and tertiary (hypothalamic) congenital or acquired hypothyroidism. It is also indicated as an adjunct to surgery and radioiodine therapy in the management of thyrotropin-dependent well-differentiated thyroid cancer.
Also known as(155)
3,3',5,5'-Tetraiodo-L-thyronine
3,5,3',5'-Tetraiodo-L-thyronine
4-(4-Hydroxy-3,5-diiodophenoxy)-3,5-diiodo-L-phenylalanine
L-T4
L-Thyroxine
Levothyroxin
Levothyroxine
LT4
Dosage forms(270)
Tablet (Oral) — 100.000 mcg
Tablet (Oral) — 10.000 mcg
Tablet (Oral) — 100 UG
Tablet (Oral) — 125 UG
Tablet (Oral) — 150 UG
Tablet (Oral) — 50 UG
Tablet (Oral) — 75 UG
Tablet (Oral) — 100 mcg/1
Molecular properties(19)
Drug interactions(765)
Known interactions with other medications. Always consult a healthcare professional.
The serum concentration of Afatinib can be decreased when it is combined with Levothyroxine.
Brentuximab vedotin
Unknown severity
The serum concentration of Brentuximab vedotin can be decreased when it is combined with Levothyroxine.
Dabigatran etexilate
Unknown severity
The serum concentration of Dabigatran etexilate can be decreased when it is combined with Levothyroxine.
Paliperidone
Unknown severity
The serum concentration of Paliperidone can be decreased when it is combined with Levothyroxine.
Sofosbuvir
Unknown severity
The serum concentration of Sofosbuvir can be decreased when it is combined with Levothyroxine.
Sucralfate
Moderate
Sucralfate can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Aluminum hydroxide
Unknown severity
The serum concentration of Levothyroxine can be decreased when it is combined with Aluminum hydroxide.
The serum concentration of Levothyroxine can be decreased when it is combined with Orlistat.
Raloxifene
Moderate
Raloxifene can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
The serum concentration of Levothyroxine can be decreased when it is combined with Sevelamer.
Iron sucrose
Unknown severity
The serum concentration of Levothyroxine can be decreased when it is combined with Iron sucrose.
Ledipasvir
Unknown severity
The serum concentration of Ledipasvir can be decreased when it is combined with Levothyroxine.
Cimetidine
Moderate
Cimetidine can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Nizatidine
Moderate
Nizatidine can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Ranitidine
Moderate
Ranitidine can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Famotidine
Moderate
Famotidine can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Methantheline
Moderate
Methantheline can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Aluminium can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Magnesium oxide
Moderate
Magnesium oxide can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Sodium bicarbonate
Moderate
Sodium bicarbonate can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Calcium carbonate
Moderate
Calcium carbonate can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Metiamide can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Roxatidine acetate
Moderate
Roxatidine acetate can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Magaldrate
Moderate
Magaldrate can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Magnesium hydroxide
Moderate
Magnesium hydroxide can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Magnesium trisilicate
Moderate
Magnesium trisilicate can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Magnesium carbonate
Moderate
Magnesium carbonate can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Lafutidine
Moderate
Lafutidine can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Lavoltidine
Moderate
Lavoltidine can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Bismuth subnitrate
Moderate
Bismuth subnitrate can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Magnesium silicate
Moderate
Magnesium silicate can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Aluminium acetoacetate
Moderate
Aluminium acetoacetate can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Hydrotalcite
Moderate
Hydrotalcite can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Magnesium peroxide
Moderate
Magnesium peroxide can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Almasilate
Moderate
Almasilate can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Aluminium glycinate
Moderate
Aluminium glycinate can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Aloglutamol
Moderate
Aloglutamol can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Niperotidine
Moderate
Niperotidine can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Calcium silicate
Moderate
Calcium silicate can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Aluminium phosphate
Moderate
Aluminium phosphate can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Omeprazole
Moderate
Omeprazole can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Lansoprazole
Moderate
Lansoprazole can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Pantoprazole
Moderate
Pantoprazole can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Esomeprazole
Moderate
Esomeprazole can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Rabeprazole
Moderate
Rabeprazole can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Dexlansoprazole
Moderate
Dexlansoprazole can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Dexrabeprazole
Moderate
Dexrabeprazole can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Sodium zirconium cyclosilicate can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Vonoprazan
Moderate
Vonoprazan can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Iron Dextran
Moderate
Iron Dextran can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.
Showing 50 of 765 interactions
Food & lifestyle interactions
Advice
Avoid calcium supplements/calcium rich foods. Calcium may interfere with the absorption of this drug by forming an insoluble complex. Separate medication administration by at least 4 hours.
Avoid Grapefruit
Avoid grapefruit products. Grapefruit may delay the absorption of this medication.
Advice
Avoid iron supplements. Iron may interfere with the absorption of this drug by forming an insoluble complex. Separate medication administration by at least 4 hours.
Advice
Avoid multivalent ions. Examples include iron, magnesium, and calcium. These are often found in antacids, vitamins, and supplements - separate medication administration by at least 4 hours.
Advice
Do not take with bran and high fiber foods. Dietary fiber, soybean flour, cottonseed meal, and walnuts may reduce the absorption of levothyroxine.
Empty Stomach
Take on an empty stomach. Levothyroxine should be taken on an empty stomach 30-60 minutes prior to the first meal of the day.
Toxicity & overdose
LD50=20 mg/kg (orally in rat). Hypermetabolic state indistinguishable from thyrotoxicosis of endogenous origin. Symptoms of thyrotoxicosis include weight loss, increased appetite, palpitations, nervousness, diarrhea, abdominal cramps, sweating, tachycardia, increased pulse and blood pressure, cardiac arrhythmias, tremors, insomnia, heat intolerance, fever, and menstrual irregularities.
How it works
Mechanism of action
Levothyroxine is a synthetically prepared levo-isomer of the thyroid hormone thyroxine (T4, a tetra-iodinated tyrosine derivative) that acts as a replacement in deficiency syndromes such as hypothyroidism. T4 is the major hormone secreted from the thyroid gland and is chemically identical to the naturally secreted T4: it increases metabolic rate, decreases thyroid-stimulating hormone (TSH) production from the anterior lobe of the pituitary gland, and, in peripheral tissues, is converted to T3. Thyroxine is released from its precursor protein thyroglobulin through proteolysis and secreted into the blood where is it then peripherally deiodinated to form triiodothyronine (T3) which exerts a broad spectrum of stimulatory effects on cell metabolism. T4 and T3 have a relative potency of ~1:4.
Thyroid hormone increases the metabolic rate of cells of all tissues in the body. In the fetus and newborn, thyroid hormone is important for the growth and development of all tissues including bones and the brain. In adults, thyroid hormone helps to maintain brain function, food metabolism, and body temperature, among other effects. The symptoms of thyroid deficiency relieved by levothyroxine include slow speech, lack of energy, weight gain, hair loss, dry thick skin and unusual sensitivity to cold.
The thyroid hormones have been shown to exert both genomic and non-genomic effects.[A179950] They exert their genomic effects by diffusing into the cell nucleus and binding to thyroid hormone receptors in DNA regions called thyroid hormone response elements (TREs) near genes.[A179605] This complex of T4, T3, DNA, and other coregulatory proteins causes a conformational change and a resulting shift in transcriptional regulation of nearby genes, synthesis of messenger RNA, and cytoplasmic protein production.[A179605][A179935] For example, in cardiac tissues T3 has been shown to regulate the genes for α- and β-myosin heavy chains, production of the sarcoplasmic reticulum proteins calcium-activated ATPase (Ca2+-ATPase) and phospholamban, β-adrenergic receptors, guanine-nucleotide regulatory proteins, and adenylyl cyclase types V and VI as well as several plasma-membrane ion transporters, such as Na+/K+–ATPase, Na+/Ca2+ exchanger, and voltage-gated potassium channels, including Kv1.5, Kv4.2, and Kv4.3. [A179938] As a result, many cardiac functions including heart rate, cardiac output, and systemic vascular resistance are closely linked to thyroid status.
The non-genomic actions of the thyroid hormones have been shown to occur through binding to a plasma membrane receptor integrin aVb3 at the Arg-Gly-Asp recognition site.[A179959] From the cell-surface, T4 binding to integrin results in down-stream effects including activation of mitogen-activated protein kinase (MAPK; ERK1/2) and causes subsequent effects on cellular/nuclear events including angiogenesis and tumor cell proliferation.[A179935][A179956]
Thyroid hormone increases the metabolic rate of cells of all tissues in the body. In the fetus and newborn, thyroid hormone is important for the growth and development of all tissues including bones and the brain. In adults, thyroid hormone helps to maintain brain function, food metabolism, and body temperature, among other effects. The symptoms of thyroid deficiency relieved by levothyroxine include slow speech, lack of energy, weight gain, hair loss, dry thick skin and unusual sensitivity to cold.
The thyroid hormones have been shown to exert both genomic and non-genomic effects.[A179950] They exert their genomic effects by diffusing into the cell nucleus and binding to thyroid hormone receptors in DNA regions called thyroid hormone response elements (TREs) near genes.[A179605] This complex of T4, T3, DNA, and other coregulatory proteins causes a conformational change and a resulting shift in transcriptional regulation of nearby genes, synthesis of messenger RNA, and cytoplasmic protein production.[A179605][A179935] For example, in cardiac tissues T3 has been shown to regulate the genes for α- and β-myosin heavy chains, production of the sarcoplasmic reticulum proteins calcium-activated ATPase (Ca2+-ATPase) and phospholamban, β-adrenergic receptors, guanine-nucleotide regulatory proteins, and adenylyl cyclase types V and VI as well as several plasma-membrane ion transporters, such as Na+/K+–ATPase, Na+/Ca2+ exchanger, and voltage-gated potassium channels, including Kv1.5, Kv4.2, and Kv4.3. [A179938] As a result, many cardiac functions including heart rate, cardiac output, and systemic vascular resistance are closely linked to thyroid status.
The non-genomic actions of the thyroid hormones have been shown to occur through binding to a plasma membrane receptor integrin aVb3 at the Arg-Gly-Asp recognition site.[A179959] From the cell-surface, T4 binding to integrin results in down-stream effects including activation of mitogen-activated protein kinase (MAPK; ERK1/2) and causes subsequent effects on cellular/nuclear events including angiogenesis and tumor cell proliferation.[A179935][A179956]
Pharmacodynamics
Oral levothyroxine is a synthetic hormone that exerts the same physiologic effect as endogenous T4, thereby maintaining normal T4 levels when a deficiency is present.
Levothyroxine has a narrow therapeutic index and is titrated to maintain a euthyroid state with TSH (thyroid stimulating hormone) within a therapeutic range of 0.4–4.0 mIU/L.[A35722] Over- or under-treatment with levothyroxine may have negative effects on growth and development, cardiovascular function, bone metabolism, reproductive function, cognitive function, emotional state, gastrointestinal function and glucose and lipid metabolism. The dose of levothyroxine should be titrated slowly and carefully and patients should be monitored for their response to titration to avoid these effects. TSH levels should be monitored at least yearly to avoid over-treating with levothyroxine which can result in hyperthyroidism (TSH <0.1mIU/L) and symptoms of increased heart rate, diarrhea, tremor, hypercalcemia, and weakness to name a few.[F4636]
As many cardiac functions including heart rate, cardiac output, and systemic vascular resistance are closely linked to thyroid status,[A179938] over-treatment with levothyroxine may result in increases 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. In populations with any cardiac concerns, levothyroxine should be initiated at lower doses than those recommended in younger individuals or in patients without cardiac disease. Patients receiving concomitant levothyroxine and sympathomimetic agents should be monitored for signs and symptoms of coronary insufficiency. If cardiac symptoms develop or worsen, reduce the levothyroxine dose or withhold for one week and restart at a lower dose.F4636
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 levothyroxine that achieves the desired clinical and biochemical response to mitigate this risk.
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 levothyroxine.
Levothyroxine has a narrow therapeutic index and is titrated to maintain a euthyroid state with TSH (thyroid stimulating hormone) within a therapeutic range of 0.4–4.0 mIU/L.[A35722] Over- or under-treatment with levothyroxine may have negative effects on growth and development, cardiovascular function, bone metabolism, reproductive function, cognitive function, emotional state, gastrointestinal function and glucose and lipid metabolism. The dose of levothyroxine should be titrated slowly and carefully and patients should be monitored for their response to titration to avoid these effects. TSH levels should be monitored at least yearly to avoid over-treating with levothyroxine which can result in hyperthyroidism (TSH <0.1mIU/L) and symptoms of increased heart rate, diarrhea, tremor, hypercalcemia, and weakness to name a few.[F4636]
As many cardiac functions including heart rate, cardiac output, and systemic vascular resistance are closely linked to thyroid status,[A179938] over-treatment with levothyroxine may result in increases 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. In populations with any cardiac concerns, levothyroxine should be initiated at lower doses than those recommended in younger individuals or in patients without cardiac disease. Patients receiving concomitant levothyroxine and sympathomimetic agents should be monitored for signs and symptoms of coronary insufficiency. If cardiac symptoms develop or worsen, reduce the levothyroxine dose or withhold for one week and restart at a lower dose.F4636
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 levothyroxine that achieves the desired clinical and biochemical response to mitigate this risk.
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 levothyroxine.
Pharmacokinetics
How the body processes this drug — absorption, distribution, metabolism, and elimination
Absorption
Absorption of orally administered T4 from the gastrointestinal tract ranges from 40% to 80% with the majority of the levothyroxine dose absorbed from the jejunum and upper ileum. T4 absorption is increased by fasting, and decreased in malabsorption syndromes and by certain foods such as soybeans, milk, and dietary fiber. Absorption may also decrease with age.
In addition, many drugs affect T4 absorption including bile acide sequestrants, sucralfate, proton pump inhibitors, and minerals such as calcium (including in yogurt and milk products)[A179617], magnesium, iron, and aluminum supplements. To prevent the formation of insoluble chelates, levothyroxine should generally be taken on an empty stomach at least 2 hours before a meal and separated by at least 4 hours from any interacting agents.
In addition, many drugs affect T4 absorption including bile acide sequestrants, sucralfate, proton pump inhibitors, and minerals such as calcium (including in yogurt and milk products)[A179617], magnesium, iron, and aluminum supplements. To prevent the formation of insoluble chelates, levothyroxine should generally be taken on an empty stomach at least 2 hours before a meal and separated by at least 4 hours from any interacting agents.
Half-life
T4 half-life is 6 to 7 days. T3 half-life is 1 to 2 days.F4636
Protein binding
Circulating thyroid hormones are greater than 99% bound to plasma proteins, including thyroxine-binding globulin (TBG), thyroxine-binding prealbumin (TBPA) and albumin (TBA). The higher affinity of both TBG and TBPA for T4 partially explains the higher serum levels, slower metabolic clearance and longer half-life of T4 compared to T3. Protein-bound thyroid hormones exist in reverse equilibrium with small amounts of free hormone where only unbound hormone is metabolically active.F4636
Metabolism
Approximately 70% of secreted T4 is deiodinated to equal amounts of T3 and reverse triiodothyronine (rT3), which is calorigenically inactive. T4 is slowly eliminated through its major metabolic pathway to T3 via sequential deiodination, where approximately 80% of circulating T3 is derived from peripheral T4. 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.
Elimination of T4 and T3 involves hepatic conjugation to glucuronic and sulfuric acids.
The hormones undergo enterohepatic circulation as conjugates are hydrolyzed in the intestine and reabsorbed. Conjugated compounds that reach the colon are hydrolyzed and eliminated as free compounds in the feces. Other minor T4 metabolites have been identified. F4636
Elimination of T4 and T3 involves hepatic conjugation to glucuronic and sulfuric acids.
The hormones undergo enterohepatic circulation as conjugates are hydrolyzed in the intestine and reabsorbed. Conjugated compounds that reach the colon are hydrolyzed and eliminated as free compounds in the feces. Other minor T4 metabolites have been identified. F4636
Route of elimination
Thyroid hormones are primarily eliminated by the kidneys. A portion of the conjugated hormone reaches the colon unchanged and is eliminated in the feces. Approximately 20% of T4 is eliminated in the stool.
Urinary excretion of T4 decreases with age.F4636
Urinary excretion of T4 decreases with age.F4636
Drug targets(4)
Proteins and enzymes this drug interacts with in the body
Integrin alpha-V
ITGAV
binder
Specific functioncoreceptor activity
Cellular location
Cell membrane
General function & pharmacology
The alpha-V (ITGAV) integrins are receptors for vitronectin, cytotactin, fibronectin, fibrinogen, laminin, matrix metalloproteinase-2, osteopontin, osteomodulin, prothrombin, thrombospondin and vWF. They recognize the sequence R-G-D in a wide array of ligands. ITGAV:ITGB3 binds to fractalkine (CX3CL1) and may act as its coreceptor in CX3CR1-dependent fractalkine signaling .
PMID:23125415
ITGAV:ITGB3 binds to NRG1 (via EGF domain) and this binding is essential for NRG1-ERBB signaling .
PMID:20682778
ITGAV:ITGB3 binds to FGF1 and this binding is essential for FGF1 signaling .
PMID:18441324
ITGAV:ITGB3 binds to FGF2 and this binding is essential for FGF2 signaling .
PMID:28302677
ITGAV:ITGB3 binds to IGF1 and this binding is essential for IGF1 signaling .
PMID:19578119
ITGAV:ITGB3 binds to IGF2 and this binding is essential for IGF2 signaling .
PMID:28873464
ITGAV:ITGB3 binds to IL1B and this binding is essential for IL1B signaling .
PMID:29030430
ITGAV:ITGB3 binds to PLA2G2A via a site (site 2) which is distinct from the classical ligand-binding site (site 1) and this induces integrin conformational changes and enhanced ligand binding to site 1 .
PMID:18635536 PMID:25398877
ITGAV:ITGB3 and ITGAV:ITGB6 act as receptors for fibrillin-1 (FBN1) and mediate R-G-D-dependent cell adhesion to FBN1 .
PMID:12807887 PMID:17158881
Integrin alpha-V/beta-6 or alpha-V/beta-8 (ITGAV:ITGB6 or ITGAV:ITGB8) mediates R-G-D-dependent release of transforming growth factor beta-1 (TGF-beta-1) from regulatory Latency-associated peptide (LAP), thereby playing a key role in TGF-beta-1 activation .
PMID:15184403 PMID:22278742 PMID:28117447
ITGAV:ITGB3 acts as a receptor for CD40LG .
PMID:31331973
ITGAV:ITGB3 acts as a receptor for IBSP and promotes cell adhesion and migration to IBSP PMID:10640428
PMID:23125415
ITGAV:ITGB3 binds to NRG1 (via EGF domain) and this binding is essential for NRG1-ERBB signaling .
PMID:20682778
ITGAV:ITGB3 binds to FGF1 and this binding is essential for FGF1 signaling .
PMID:18441324
ITGAV:ITGB3 binds to FGF2 and this binding is essential for FGF2 signaling .
PMID:28302677
ITGAV:ITGB3 binds to IGF1 and this binding is essential for IGF1 signaling .
PMID:19578119
ITGAV:ITGB3 binds to IGF2 and this binding is essential for IGF2 signaling .
PMID:28873464
ITGAV:ITGB3 binds to IL1B and this binding is essential for IL1B signaling .
PMID:29030430
ITGAV:ITGB3 binds to PLA2G2A via a site (site 2) which is distinct from the classical ligand-binding site (site 1) and this induces integrin conformational changes and enhanced ligand binding to site 1 .
PMID:18635536 PMID:25398877
ITGAV:ITGB3 and ITGAV:ITGB6 act as receptors for fibrillin-1 (FBN1) and mediate R-G-D-dependent cell adhesion to FBN1 .
PMID:12807887 PMID:17158881
Integrin alpha-V/beta-6 or alpha-V/beta-8 (ITGAV:ITGB6 or ITGAV:ITGB8) mediates R-G-D-dependent release of transforming growth factor beta-1 (TGF-beta-1) from regulatory Latency-associated peptide (LAP), thereby playing a key role in TGF-beta-1 activation .
PMID:15184403 PMID:22278742 PMID:28117447
ITGAV:ITGB3 acts as a receptor for CD40LG .
PMID:31331973
ITGAV:ITGB3 acts as a receptor for IBSP and promotes cell adhesion and migration to IBSP PMID:10640428
Integrin beta-3
ITGB3
binder
Specific functioncell adhesion molecule binding
Cellular location
Cell membrane
General function & pharmacology
Integrin alpha-V/beta-3 (ITGAV:ITGB3) is a receptor for cytotactin, fibronectin, laminin, matrix metalloproteinase-2, osteopontin, osteomodulin, prothrombin, thrombospondin, vitronectin and von Willebrand factor. Integrin alpha-IIb/beta-3 (ITGA2B:ITGB3) is a receptor for fibronectin, fibrinogen, plasminogen, prothrombin, thrombospondin and vitronectin. Integrins alpha-IIb/beta-3 and alpha-V/beta-3 recognize the sequence R-G-D in a wide array of ligands.
Integrin alpha-IIb/beta-3 recognizes the sequence H-H-L-G-G-G-A-K-Q-A-G-D-V in fibrinogen gamma chain (By similarity). Following activation integrin alpha-IIb/beta-3 brings about platelet/platelet interaction through binding of soluble fibrinogen .
PMID:9111081
This step leads to rapid platelet aggregation which physically plugs ruptured endothelial surface. Fibrinogen binding enhances SELP expression in activated platelets (By similarity).
ITGAV:ITGB3 binds to fractalkine (CX3CL1) and acts as its coreceptor in CX3CR1-dependent fractalkine signaling .
PMID:23125415 PMID:24789099
ITGAV:ITGB3 binds to NRG1 (via EGF domain) and this binding is essential for NRG1-ERBB signaling .
PMID:20682778
ITGAV:ITGB3 binds to FGF1 and this binding is essential for FGF1 signaling .
PMID:18441324
ITGAV:ITGB3 binds to FGF2 and this binding is essential for FGF2 signaling .
PMID:28302677
ITGAV:ITGB3 binds to IGF1 and this binding is essential for IGF1 signaling .
PMID:19578119
ITGAV:ITGB3 binds to IGF2 and this binding is essential for IGF2 signaling .
PMID:28873464
ITGAV:ITGB3 binds to IL1B and this binding is essential for IL1B signaling .
PMID:29030430
ITGAV:ITGB3 binds to PLA2G2A via a site (site 2) which is distinct from the classical ligand-binding site (site 1) and this induces integrin conformational changes and enhanced ligand binding to site 1 .
PMID:18635536 PMID:25398877
ITGAV:ITGB3 acts as a receptor for fibrillin-1 (FBN1) and mediates R-G-D-dependent cell adhesion to FBN1 .
PMID:12807887
In brain, plays a role in synaptic transmission and plasticity. Involved in the regulation of the serotonin neurotransmission, is required to localize to specific compartments within the synapse the serotonin receptor SLC6A4 and for an appropriate reuptake of serotonin. Controls excitatory synaptic strength by regulating GRIA2-containing AMPAR endocytosis, which affects AMPAR abundance and composition (By similarity).
ITGAV:ITGB3 act as a receptor for CD40LG .
PMID:31331973
ITGAV:ITGB3 acts as a receptor for IBSP and promotes cell adhesion and migration to IBSP PMID:10640428
Integrin alpha-IIb/beta-3 recognizes the sequence H-H-L-G-G-G-A-K-Q-A-G-D-V in fibrinogen gamma chain (By similarity). Following activation integrin alpha-IIb/beta-3 brings about platelet/platelet interaction through binding of soluble fibrinogen .
PMID:9111081
This step leads to rapid platelet aggregation which physically plugs ruptured endothelial surface. Fibrinogen binding enhances SELP expression in activated platelets (By similarity).
ITGAV:ITGB3 binds to fractalkine (CX3CL1) and acts as its coreceptor in CX3CR1-dependent fractalkine signaling .
PMID:23125415 PMID:24789099
ITGAV:ITGB3 binds to NRG1 (via EGF domain) and this binding is essential for NRG1-ERBB signaling .
PMID:20682778
ITGAV:ITGB3 binds to FGF1 and this binding is essential for FGF1 signaling .
PMID:18441324
ITGAV:ITGB3 binds to FGF2 and this binding is essential for FGF2 signaling .
PMID:28302677
ITGAV:ITGB3 binds to IGF1 and this binding is essential for IGF1 signaling .
PMID:19578119
ITGAV:ITGB3 binds to IGF2 and this binding is essential for IGF2 signaling .
PMID:28873464
ITGAV:ITGB3 binds to IL1B and this binding is essential for IL1B signaling .
PMID:29030430
ITGAV:ITGB3 binds to PLA2G2A via a site (site 2) which is distinct from the classical ligand-binding site (site 1) and this induces integrin conformational changes and enhanced ligand binding to site 1 .
PMID:18635536 PMID:25398877
ITGAV:ITGB3 acts as a receptor for fibrillin-1 (FBN1) and mediates R-G-D-dependent cell adhesion to FBN1 .
PMID:12807887
In brain, plays a role in synaptic transmission and plasticity. Involved in the regulation of the serotonin neurotransmission, is required to localize to specific compartments within the synapse the serotonin receptor SLC6A4 and for an appropriate reuptake of serotonin. Controls excitatory synaptic strength by regulating GRIA2-containing AMPAR endocytosis, which affects AMPAR abundance and composition (By similarity).
ITGAV:ITGB3 act as a receptor for CD40LG .
PMID:31331973
ITGAV:ITGB3 acts as a receptor for IBSP and promotes cell adhesion and migration to IBSP PMID:10640428
Thyroid hormone receptor alpha
THRA
agonist
Specific functionchromatin DNA binding
Cellular location
Nucleus
General function & pharmacology
Nuclear hormone receptor that can act as a repressor or activator of transcription. High affinity receptor for thyroid hormones, including triiodothyronine and thyroxine
Thyroid hormone receptor beta
THRB
agonist
Specific functionchromatin DNA binding
Cellular location
Nucleus
General function & pharmacology
Nuclear hormone receptor that can act as a repressor or activator of transcription. High affinity receptor for thyroid hormones, including triiodothyronine and thyroxine
Metabolizing enzymes(3)
Enzymes involved in drug metabolism — important for understanding drug interactions
Enzyme activity key
substrate
inhibitor
inducer
UGT1A1UDP-glucuronosyltransferase 1A1
substrate
ABCB1ATP-dependent translocase ABCB1
inducer
CYP2C8Cytochrome P450 2C8
inhibitor
Transporters(8)
Proteins that transport this drug across cell membranes
Solute carrier organic anion transporter family member 1C1
SLCO1C1
substrate
Specific functionbile acid transmembrane transporter activity
Cellular location
Cell membrane
General function & pharmacology
Mediates the Na(+)-independent high affinity transport of organic anions such as the thyroid hormones L-thyroxine (T4), L-thyroxine sulfate (T4S), and 3,3',5'-triiodo-L-thyronine (reverse T3, rT3) at the plasma membrane .
PMID:12351693 PMID:18566113 PMID:19129463
Regulates T4 levels in different brain regions by transporting T4, and also by serving as an export pump for T4S, which is a source of T4 after hydrolysis by local sulfatases .
PMID:18566113
Increases the access of these substrates to the intracellular sites where they are metabolized by the deiodinases .
PMID:18566113
Other potential substrates, such as triiodothyronine (T3), 17-beta-glucuronosyl estradiol (17beta-estradiol 17-O-(beta-D-glucuronate)), estrone-3-sulfate (E1S) and sulfobromophthalein (BSP) are transported with much lower efficiency .
PMID:12351693 PMID:19129463
Transports T4 and E1S in a pH-insensitive manner .
PMID:19129463
Facilitates the transport of thyroid hormones across the blood-brain barrier and into glia and neuronal cells in the brain PMID:30296914
PMID:12351693 PMID:18566113 PMID:19129463
Regulates T4 levels in different brain regions by transporting T4, and also by serving as an export pump for T4S, which is a source of T4 after hydrolysis by local sulfatases .
PMID:18566113
Increases the access of these substrates to the intracellular sites where they are metabolized by the deiodinases .
PMID:18566113
Other potential substrates, such as triiodothyronine (T3), 17-beta-glucuronosyl estradiol (17beta-estradiol 17-O-(beta-D-glucuronate)), estrone-3-sulfate (E1S) and sulfobromophthalein (BSP) are transported with much lower efficiency .
PMID:12351693 PMID:19129463
Transports T4 and E1S in a pH-insensitive manner .
PMID:19129463
Facilitates the transport of thyroid hormones across the blood-brain barrier and into glia and neuronal cells in the brain PMID:30296914
Monocarboxylate transporter 8
SLC16A2
inhibitor
Specific functionamino acid transmembrane transporter activity
Cellular location
Cell membrane
General function & pharmacology
Specific thyroid hormone transmembrane transporter, that mediates both uptake and efflux of thyroid hormones across the cell membrane independently of pH or a Na(+) gradient. Major substrates are the iodothyronines T3 and T4 and to a lesser extent rT3 and 3,3-diiodothyronine (3,3'-T2) .
PMID:16887882 PMID:18337592 PMID:20628049 PMID:23550058 PMID:26426690 PMID:27805744 PMID:31436139
Acts as an important mediator of thyroid hormone transport, especially T3, through the blood-brain barrier (Probable) PMID:28526555
PMID:16887882 PMID:18337592 PMID:20628049 PMID:23550058 PMID:26426690 PMID:27805744 PMID:31436139
Acts as an important mediator of thyroid hormone transport, especially T3, through the blood-brain barrier (Probable) PMID:28526555
ATP-dependent translocase ABCB1
ABCB1
inducer
Specific functionABC-type xenobiotic transporter activity
Cellular location
Cell membrane
General function & pharmacology
Translocates drugs and phospholipids across the membrane .
PMID:2897240 PMID:35970996 PMID:8898203 PMID:9038218 PMID:35507548
Catalyzes the flop of phospholipids from the cytoplasmic to the exoplasmic leaflet of the apical membrane. Participates mainly to the flop of phosphatidylcholine, phosphatidylethanolamine, beta-D-glucosylceramides and sphingomyelins .
PMID:8898203
Energy-dependent efflux pump responsible for decreased drug accumulation in multidrug-resistant cells PMID:2897240 PMID:35970996 PMID:9038218
PMID:2897240 PMID:35970996 PMID:8898203 PMID:9038218 PMID:35507548
Catalyzes the flop of phospholipids from the cytoplasmic to the exoplasmic leaflet of the apical membrane. Participates mainly to the flop of phosphatidylcholine, phosphatidylethanolamine, beta-D-glucosylceramides and sphingomyelins .
PMID:8898203
Energy-dependent efflux pump responsible for decreased drug accumulation in multidrug-resistant cells PMID:2897240 PMID:35970996 PMID:9038218
Solute carrier organic anion transporter family member 1A2
SLCO1A2
substrate
Specific functionbile acid transmembrane transporter activity
Cellular location
Cell membrane
General function & pharmacology
Na(+)-independent transporter that mediates the cellular uptake of a broad range of organic anions such as the endogenous bile salts cholate and deoxycholate, either in their unconjugated or conjugated forms (taurocholate and glycocholate), at the plasmam membrane .
PMID:19129463 PMID:7557095
Responsible for intestinal absorption of bile acids (By similarity). Transports dehydroepiandrosterone 3-sulfate (DHEAS), a major circulating steroid secreted by the adrenal cortex, as well as estrone 3-sulfate and 17beta-estradiol 17-O-(beta-D-glucuronate) .
PMID:11159893 PMID:12568656 PMID:19129463 PMID:23918469 PMID:25560245 PMID:9539145
Mediates apical uptake of all-trans-retinol (atROL) across human retinal pigment epithelium, which is essential to maintaining the integrity of the visual cycle and thus vision .
PMID:25560245
Involved in the uptake of clinically used drugs .
PMID:17301733 PMID:20686826 PMID:27777271
Capable of thyroid hormone transport (both T3 or 3,3',5'-triiodo-L-thyronine, and T4 or L-tyroxine) .
PMID:19129463 PMID:20358049
Also transports prostaglandin E2 .
PMID:19129463
Plays roles in blood-brain and -cerebrospinal fluid barrier transport of organic anions and signal mediators, and in hormone uptake by neural cells (By similarity). May also play a role in the reuptake of neuropeptides such as substance P/TAC1 and vasoactive intestinal peptide/VIP released from retinal neurons .
PMID:25132355
May play an important role in plasma and tissue distribution of the structurally diverse chemotherapeutic drugs methotrexate and paclitaxel .
PMID:23243220
Shows a pH-sensitive substrate specificity which may be ascribed to the protonation state of the binding site and leads to a stimulation of substrate transport in an acidic microenvironment .
PMID:19129463
Hydrogencarbonate/HCO3(-) acts as the probable counteranion that exchanges for organic anions .
PMID:19129463
May contribute to regulate the transport of organic compounds in testis across the blood-testis-barrier (Probable)
PMID:19129463 PMID:7557095
Responsible for intestinal absorption of bile acids (By similarity). Transports dehydroepiandrosterone 3-sulfate (DHEAS), a major circulating steroid secreted by the adrenal cortex, as well as estrone 3-sulfate and 17beta-estradiol 17-O-(beta-D-glucuronate) .
PMID:11159893 PMID:12568656 PMID:19129463 PMID:23918469 PMID:25560245 PMID:9539145
Mediates apical uptake of all-trans-retinol (atROL) across human retinal pigment epithelium, which is essential to maintaining the integrity of the visual cycle and thus vision .
PMID:25560245
Involved in the uptake of clinically used drugs .
PMID:17301733 PMID:20686826 PMID:27777271
Capable of thyroid hormone transport (both T3 or 3,3',5'-triiodo-L-thyronine, and T4 or L-tyroxine) .
PMID:19129463 PMID:20358049
Also transports prostaglandin E2 .
PMID:19129463
Plays roles in blood-brain and -cerebrospinal fluid barrier transport of organic anions and signal mediators, and in hormone uptake by neural cells (By similarity). May also play a role in the reuptake of neuropeptides such as substance P/TAC1 and vasoactive intestinal peptide/VIP released from retinal neurons .
PMID:25132355
May play an important role in plasma and tissue distribution of the structurally diverse chemotherapeutic drugs methotrexate and paclitaxel .
PMID:23243220
Shows a pH-sensitive substrate specificity which may be ascribed to the protonation state of the binding site and leads to a stimulation of substrate transport in an acidic microenvironment .
PMID:19129463
Hydrogencarbonate/HCO3(-) acts as the probable counteranion that exchanges for organic anions .
PMID:19129463
May contribute to regulate the transport of organic compounds in testis across the blood-testis-barrier (Probable)
Solute carrier organic anion transporter family member 1B1
SLCO1B1
substrate
Specific functionbile acid transmembrane transporter activity
Cellular location
Basolateral cell membrane
General function & pharmacology
Mediates the Na(+)-independent uptake of organic anions .
PMID:10358072 PMID:15159445 PMID:17412826
Shows broad substrate specificity, can transport both organic anions such as bile acid taurocholate (cholyltaurine) and conjugated steroids (dehydroepiandrosterone 3-sulfate, 17-beta-glucuronosyl estradiol, and estrone 3-sulfate), as well as eicosanoids (prostaglandin E2, thromboxane B2, leukotriene C4, and leukotriene E4), and thyroid hormones (T4/L-thyroxine, and T3/3,3',5'-triiodo-L-thyronine) .
PMID:10358072 PMID:10601278 PMID:10873595 PMID:11159893 PMID:12196548 PMID:12568656 PMID:15159445 PMID:15970799 PMID:16627748 PMID:17412826 PMID:19129463 PMID:26979622
Can take up bilirubin glucuronides from plasma into the liver, contributing to the detoxification-enhancing liver-blood shuttling loop .
PMID:22232210
Involved in the clearance of endogenous and exogenous substrates from the liver .
PMID:10358072 PMID:10601278
Transports coproporphyrin I and III, by-products of heme synthesis, and may be involved in their hepatic disposition .
PMID:26383540
May contribute to regulate the transport of organic compounds in testes across the blood-testis-barrier (Probable). Can transport HMG-CoA reductase inhibitors (also known as statins), such as pravastatin and pitavastatin, a clinically important class of hypolipidemic drugs .
PMID:10601278 PMID:15159445 PMID:15970799
May play an important role in plasma and tissue distribution of the structurally diverse chemotherapeutic drug methotrexate .
PMID:23243220
May also transport antihypertension agents, such as the angiotensin-converting enzyme (ACE) inhibitor prodrug enalapril, and the highly selective angiotensin II AT1-receptor antagonist valsartan, in the liver .
PMID:16624871 PMID:16627748
Shows a pH-sensitive substrate specificity towards prostaglandin E2 and T4 which may be ascribed to the protonation state of the binding site and leads to a stimulation of substrate transport in an acidic microenvironment .
PMID:19129463
Hydrogencarbonate/HCO3(-) acts as the probable counteranion that exchanges for organic anions PMID:19129463
PMID:10358072 PMID:15159445 PMID:17412826
Shows broad substrate specificity, can transport both organic anions such as bile acid taurocholate (cholyltaurine) and conjugated steroids (dehydroepiandrosterone 3-sulfate, 17-beta-glucuronosyl estradiol, and estrone 3-sulfate), as well as eicosanoids (prostaglandin E2, thromboxane B2, leukotriene C4, and leukotriene E4), and thyroid hormones (T4/L-thyroxine, and T3/3,3',5'-triiodo-L-thyronine) .
PMID:10358072 PMID:10601278 PMID:10873595 PMID:11159893 PMID:12196548 PMID:12568656 PMID:15159445 PMID:15970799 PMID:16627748 PMID:17412826 PMID:19129463 PMID:26979622
Can take up bilirubin glucuronides from plasma into the liver, contributing to the detoxification-enhancing liver-blood shuttling loop .
PMID:22232210
Involved in the clearance of endogenous and exogenous substrates from the liver .
PMID:10358072 PMID:10601278
Transports coproporphyrin I and III, by-products of heme synthesis, and may be involved in their hepatic disposition .
PMID:26383540
May contribute to regulate the transport of organic compounds in testes across the blood-testis-barrier (Probable). Can transport HMG-CoA reductase inhibitors (also known as statins), such as pravastatin and pitavastatin, a clinically important class of hypolipidemic drugs .
PMID:10601278 PMID:15159445 PMID:15970799
May play an important role in plasma and tissue distribution of the structurally diverse chemotherapeutic drug methotrexate .
PMID:23243220
May also transport antihypertension agents, such as the angiotensin-converting enzyme (ACE) inhibitor prodrug enalapril, and the highly selective angiotensin II AT1-receptor antagonist valsartan, in the liver .
PMID:16624871 PMID:16627748
Shows a pH-sensitive substrate specificity towards prostaglandin E2 and T4 which may be ascribed to the protonation state of the binding site and leads to a stimulation of substrate transport in an acidic microenvironment .
PMID:19129463
Hydrogencarbonate/HCO3(-) acts as the probable counteranion that exchanges for organic anions PMID:19129463
Solute carrier organic anion transporter family member 4A1
SLCO4A1
substrate
Specific functionorganic anion transmembrane transporter activity
Cellular location
Cell membrane
General function & pharmacology
Organic anion antiporter with apparent broad substrate specificity. Recognizes various substrates including thyroid hormones 3,3',5-triiodo-L-thyronine (T3), L-thyroxine (T4) and 3,3',5'-triiodo-L-thyronine (rT3), conjugated steroids such as estrone 3-sulfate and estradiol 17-beta glucuronide, bile acids such as taurocholate and prostanoids such as prostaglandin E2, likely operating in a tissue-specific manner .
PMID:10873595 PMID:19129463 PMID:30343886
May be involved in uptake of metabolites from the circulation into organs such as kidney, liver or placenta. Possibly drives the selective transport of thyroid hormones and estrogens coupled to an outward glutamate gradient across the microvillous membrane of the placenta .
PMID:30343886
The transport mechanism, its electrogenicity and potential tissue-specific counterions remain to be elucidated (Probable)
PMID:10873595 PMID:19129463 PMID:30343886
May be involved in uptake of metabolites from the circulation into organs such as kidney, liver or placenta. Possibly drives the selective transport of thyroid hormones and estrogens coupled to an outward glutamate gradient across the microvillous membrane of the placenta .
PMID:30343886
The transport mechanism, its electrogenicity and potential tissue-specific counterions remain to be elucidated (Probable)
Large neutral amino acids transporter small subunit 1
SLC7A5
Specific functionamino acid transmembrane transporter activity
Cellular location
Apical cell membrane
General function & pharmacology
The heterodimer with SLC3A2 functions as a sodium-independent, high-affinity transporter that mediates uptake of large neutral amino acids such as phenylalanine, tyrosine, leucine, histidine, methionine, tryptophan, valine, isoleucine and alanine .
PMID:10049700 PMID:10574970 PMID:11557028 PMID:11564694 PMID:12117417 PMID:12225859 PMID:15769744 PMID:18262359 PMID:25998567 PMID:30867591 PMID:9751058
The heterodimer with SLC3A2 mediates the uptake of L-DOPA (By similarity). Functions as an amino acid exchanger .
PMID:11557028 PMID:12117417 PMID:12225859 PMID:30867591
May play a role in the transport of L-DOPA across the blood-brain barrier (By similarity). May act as the major transporter of tyrosine in fibroblasts (Probable).
May mediate blood-to-retina L-leucine transport across the inner blood-retinal barrier (By similarity). Can mediate the transport of thyroid hormones diiodothyronine (T2), triiodothyronine (T3) and thyroxine (T4) across the cell membrane .
PMID:11564694
When associated with LAPTM4B, the heterodimer formed by SLC3A2 and SLC7A5 is recruited to lysosomes to promote leucine uptake into these organelles, and thereby mediates mTORC1 activation .
PMID:25998567
Involved in the uptake of toxic methylmercury (MeHg) when administered as the L-cysteine or D,L-homocysteine complexes .
PMID:12117417
Involved in the cellular activity of small molecular weight nitrosothiols, via the stereoselective transport of L-nitrosocysteine (L-CNSO) across the membrane PMID:15769744
PMID:10049700 PMID:10574970 PMID:11557028 PMID:11564694 PMID:12117417 PMID:12225859 PMID:15769744 PMID:18262359 PMID:25998567 PMID:30867591 PMID:9751058
The heterodimer with SLC3A2 mediates the uptake of L-DOPA (By similarity). Functions as an amino acid exchanger .
PMID:11557028 PMID:12117417 PMID:12225859 PMID:30867591
May play a role in the transport of L-DOPA across the blood-brain barrier (By similarity). May act as the major transporter of tyrosine in fibroblasts (Probable).
May mediate blood-to-retina L-leucine transport across the inner blood-retinal barrier (By similarity). Can mediate the transport of thyroid hormones diiodothyronine (T2), triiodothyronine (T3) and thyroxine (T4) across the cell membrane .
PMID:11564694
When associated with LAPTM4B, the heterodimer formed by SLC3A2 and SLC7A5 is recruited to lysosomes to promote leucine uptake into these organelles, and thereby mediates mTORC1 activation .
PMID:25998567
Involved in the uptake of toxic methylmercury (MeHg) when administered as the L-cysteine or D,L-homocysteine complexes .
PMID:12117417
Involved in the cellular activity of small molecular weight nitrosothiols, via the stereoselective transport of L-nitrosocysteine (L-CNSO) across the membrane PMID:15769744
Solute carrier organic anion transporter family member 2B1
SLCO2B1
inhibitor
Specific functionbile acid transmembrane transporter activity
Cellular location
Cell membrane
General function & pharmacology
Mediates the Na(+)-independent transport of steroid sulfate conjugates and other specific organic anions .
PMID:10873595 PMID:11159893 PMID:11932330 PMID:12724351 PMID:14610227 PMID:16908597 PMID:18501590 PMID:20507927 PMID:22201122 PMID:23531488 PMID:25132355 PMID:26383540 PMID:27576593 PMID:28408210 PMID:29871943 PMID:34628357
Responsible for the transport of estrone 3-sulfate (E1S) through the basal membrane of syncytiotrophoblast, highlighting a potential role in the placental absorption of fetal-derived sulfated steroids including the steroid hormone precursor dehydroepiandrosterone sulfate (DHEA-S) .
PMID:11932330 PMID:12409283
Also facilitates the uptake of sulfated steroids at the basal/sinusoidal membrane of hepatocytes, therefore accounting for the major part of organic anions clearance of liver .
PMID:11159893
Mediates the intestinal uptake of sulfated steroids .
PMID:12724351 PMID:28408210
Mediates the uptake of the neurosteroids DHEA-S and pregnenolone sulfate (PregS) into the endothelial cells of the blood-brain barrier as the first step to enter the brain .
PMID:16908597 PMID:25132355
Also plays a role in the reuptake of neuropeptides such as substance P/TAC1 and vasoactive intestinal peptide/VIP released from retinal neurons .
PMID:25132355
May act as a heme transporter that promotes cellular iron availability via heme oxygenase/HMOX2 and independently of TFRC .
PMID:35714613
Also transports heme by-product coproporphyrin III (CPIII), and may be involved in their hepatic disposition .
PMID:26383540
Mediates the uptake of other substrates such as prostaglandins D2 (PGD2), E1 (PGE1) and E2 (PGE2), taurocholate, L-thyroxine, leukotriene C4 and thromboxane B2 (PubMed:10873595, PubMed:14610227, PubMed:19129463, PubMed:29871943, Ref.25). May contribute to regulate the transport of organic compounds in testis across the blood-testis-barrier (Probable). Shows a pH-sensitive substrate specificity which may be ascribed to the protonation state of the binding site and leads to a stimulation of substrate transport in an acidic microenvironment .
PMID:14610227 PMID:19129463 PMID:22201122
The exact transport mechanism has not been yet deciphered but most likely involves an anion exchange, coupling the cellular uptake of organic substrate with the efflux of an anionic compound .
PMID:19129463 PMID:20507927 PMID:26277985
Hydrogencarbonate/HCO3(-) acts as a probable counteranion that exchanges for organic anions .
PMID:19129463
Cytoplasmic glutamate may also act as counteranion in the placenta .
PMID:26277985
An inwardly directed proton gradient has also been proposed as the driving force of E1S uptake with a (H(+):E1S) stoichiometry of (1:1) PMID:20507927
PMID:10873595 PMID:11159893 PMID:11932330 PMID:12724351 PMID:14610227 PMID:16908597 PMID:18501590 PMID:20507927 PMID:22201122 PMID:23531488 PMID:25132355 PMID:26383540 PMID:27576593 PMID:28408210 PMID:29871943 PMID:34628357
Responsible for the transport of estrone 3-sulfate (E1S) through the basal membrane of syncytiotrophoblast, highlighting a potential role in the placental absorption of fetal-derived sulfated steroids including the steroid hormone precursor dehydroepiandrosterone sulfate (DHEA-S) .
PMID:11932330 PMID:12409283
Also facilitates the uptake of sulfated steroids at the basal/sinusoidal membrane of hepatocytes, therefore accounting for the major part of organic anions clearance of liver .
PMID:11159893
Mediates the intestinal uptake of sulfated steroids .
PMID:12724351 PMID:28408210
Mediates the uptake of the neurosteroids DHEA-S and pregnenolone sulfate (PregS) into the endothelial cells of the blood-brain barrier as the first step to enter the brain .
PMID:16908597 PMID:25132355
Also plays a role in the reuptake of neuropeptides such as substance P/TAC1 and vasoactive intestinal peptide/VIP released from retinal neurons .
PMID:25132355
May act as a heme transporter that promotes cellular iron availability via heme oxygenase/HMOX2 and independently of TFRC .
PMID:35714613
Also transports heme by-product coproporphyrin III (CPIII), and may be involved in their hepatic disposition .
PMID:26383540
Mediates the uptake of other substrates such as prostaglandins D2 (PGD2), E1 (PGE1) and E2 (PGE2), taurocholate, L-thyroxine, leukotriene C4 and thromboxane B2 (PubMed:10873595, PubMed:14610227, PubMed:19129463, PubMed:29871943, Ref.25). May contribute to regulate the transport of organic compounds in testis across the blood-testis-barrier (Probable). Shows a pH-sensitive substrate specificity which may be ascribed to the protonation state of the binding site and leads to a stimulation of substrate transport in an acidic microenvironment .
PMID:14610227 PMID:19129463 PMID:22201122
The exact transport mechanism has not been yet deciphered but most likely involves an anion exchange, coupling the cellular uptake of organic substrate with the efflux of an anionic compound .
PMID:19129463 PMID:20507927 PMID:26277985
Hydrogencarbonate/HCO3(-) acts as a probable counteranion that exchanges for organic anions .
PMID:19129463
Cytoplasmic glutamate may also act as counteranion in the placenta .
PMID:26277985
An inwardly directed proton gradient has also been proposed as the driving force of E1S uptake with a (H(+):E1S) stoichiometry of (1:1) PMID:20507927
Carriers(3)
Proteins that carry this drug through the body
Transthyretin
TTR
Specific functionhormone activity
Cellular location
Secreted
General function & pharmacology
Thyroid hormone-binding protein. Probably transports thyroxine from the bloodstream to the brain
Thyroxine-binding globulin
SERPINA7
substrate
Specific functionserine-type endopeptidase inhibitor activity
Cellular location
Secreted
General function & pharmacology
Major thyroid hormone transport protein in serum
Albumin
ALB
Specific functionantioxidant activity
Cellular location
Secreted
General function & pharmacology
Binds water, Ca(2+), Na(+), K(+), fatty acids, hormones, bilirubin and drugs (Probable). Its main function is the regulation of the colloidal osmotic pressure of blood (Probable). Major zinc transporter in plasma, typically binds about 80% of all plasma zinc .
PMID:19021548
Major calcium and magnesium transporter in plasma, binds approximately 45% of circulating calcium and magnesium in plasma (By similarity).
Potentially has more than two calcium-binding sites and might additionally bind calcium in a non-specific manner (By similarity). The shared binding site between zinc and calcium at residue Asp-273 suggests a crosstalk between zinc and calcium transport in the blood (By similarity). The rank order of affinity is zinc > calcium > magnesium (By similarity).
Binds to the bacterial siderophore enterobactin and inhibits enterobactin-mediated iron uptake of E.coli from ferric transferrin, and may thereby limit the utilization of iron and growth of enteric bacteria such as E.coli .
PMID:6234017
Does not prevent iron uptake by the bacterial siderophore aerobactin PMID:6234017
PMID:19021548
Major calcium and magnesium transporter in plasma, binds approximately 45% of circulating calcium and magnesium in plasma (By similarity).
Potentially has more than two calcium-binding sites and might additionally bind calcium in a non-specific manner (By similarity). The shared binding site between zinc and calcium at residue Asp-273 suggests a crosstalk between zinc and calcium transport in the blood (By similarity). The rank order of affinity is zinc > calcium > magnesium (By similarity).
Binds to the bacterial siderophore enterobactin and inhibits enterobactin-mediated iron uptake of E.coli from ferric transferrin, and may thereby limit the utilization of iron and growth of enteric bacteria such as E.coli .
PMID:6234017
Does not prevent iron uptake by the bacterial siderophore aerobactin PMID:6234017
Biological pathways(1)
Scientific references(12)
Uchino H., Kanai Y., Kim D.K., Wempe M.F., Chairoungdua A., Morimoto E., Anders M.W., Endou H.
Transport of Amino Acid-Related Compounds Mediated by L-Type Amino Acid Transporter 1 (LAT1): Insights Into the Mechanisms of Substrate Recognition.
Molecular Pharmacology
200261(4):729-737. doi: 10.1124/mol.61.4.729
Cheng S.Y., Leonard J.L., Davis P.J.
Molecular aspects of thyroid hormone actions.
Endocr Review
2010 Apr31(2):139-70. doi: 10.1210/er.2009-0007. Epub 2010 Jan 5
Chon D.A., Reisman T., Weinreb J.E., Hershman J.M., Leung A.M.
Concurrent Milk Ingestion Decreases Absorption of Levothyroxine.
Thyroid
2018 Apr28(4):454-457. doi: 10.1089/thy.2017.0428. Epub 2018 Mar 28
Tang R., Wang J., Yang L., Ding X., Zhong Y., Pan J., Yang H., Mu L., Chen X., Chen Z.
Subclinical Hypothyroidism and Depression: A Systematic Review and Meta-Analysis.
Front Endocrinol (Lausanne)
2019 Jun 410:340. doi: 10.3389/fendo.2019.00340. eCollection 2019
Gottwald-Hostalek U., Uhl W., Wolna P., Kahaly G.J.
New levothyroxine formulation meeting 95-105% specification over the whole shelf-life: results from two pharmacokinetic trials.
Curr Medicine Research Opinion
2017 Feb33(2):169-174. doi: 10.1080/03007995.2016.1246434. Epub 2016 Oct 21
Osmak-Tizon L., Poussier M., Cottin Y., Rochette L.
Non-genomic actions of thyroid hormones: Molecular aspects.
Arch Cardiovasc Diseases
2014 Apr107(4):207-11. doi: 10.1016/j.acvd.2014.02.001. Epub 2014 Mar 26
Klein I., Ojamaa K.
Thyroid hormone and the cardiovascular system.
New England Journal of Medicine
2001 Feb 15344(7):501-9. doi: 10.1056/NEJM200102153440707
Kaplan M.M., Breitbart R.
Thyroid Hormone Binding to the Anterior Pituitary Gland.
Hormone and Metabolic Research
19735(01):62-62. doi: 10.1055/s-0028-1096719
Hammes S.R., Davis P.J.
Overlapping nongenomic and genomic actions of thyroid hormone and steroids.
Best Pract Research Clinical Endocrinol Metabolism
2015 Aug29(4):581-93. doi: 10.1016/j.beem.2015.04.001. Epub 2015 Apr 22
Jonklaas J., Bianco A.C., Bauer A.J., Burman K.D., Cappola A.R., Celi F.S., Cooper D.S., Kim B.W., Peeters R.P., Rosenthal M.S., Sawka A.M.
Guidelines for the treatment of hypothyroidism: prepared by the american thyroid association task force on thyroid hormone replacement.
Thyroid
2014 Dec24(12):1670-751. doi: 10.1089/thy.2014.0028
Davis P.J., Leonard J.L., Davis F.B.
Mechanisms of nongenomic actions of thyroid hormone.
Front Neuroendocrinol
2008 May29(2):211-8. doi: 10.1016/j.yfrne.2007.09.003. Epub 2007 Oct 5
Bergh J.J., Lin H.Y., Lansing L., Mohamed S.N., Davis F.B., Mousa S., Davis P.J.
Integrin alphaVbeta3 contains a cell surface receptor site for thyroid hormone that is linked to activation of mitogen-activated protein kinase and induction of angiogenesis.
Endocrinology
2005 Jul146(7):2864-71. doi: 10.1210/en.2005-0102. Epub 2005 Mar 31
ATC classification(2 codes)
ATC H03AA01
ATC H03AA51
Affected organisms(1)
Humans and other mammals
International brands(6)
Salt forms(2)
Levothyroxine sodium(DBSALT000244)
Levothyroxine sodium pentahydrate(DBSALT003388)
Experimental properties(3)
Protein Data Bank entries(26)
Commercial products(1529)
Chemical identifiers
CAS, UNII, InChI Key and database cross-references
Show
Chemical identifiers
CAS, UNII, InChI Key and database cross-references
Linked compound data from DrugBank Open Data (CC BY-NC 4.0)
Levothyroxine
Additional database identifiers
Drugs Product Database (DPD)
5325
ChemSpider
5614
BindingDB
50301375
PDB
T44
Guide to Pharmacology
2635
ZINC
ZINC000003830993
HUGO Gene Nomenclature Committee (HGNC)
HGNC:6150
GeneCards
ITGAV
GenBank Gene Database
M14648
GenBank Protein Database
340307
Guide to Pharmacology
2453
UniProt Accession
ITAV_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:6156
GenAtlas
ITGB3
GeneCards
ITGB3
GenBank Gene Database
J02703
GenBank Protein Database
306786
Guide to Pharmacology
2457
UniProt Accession
ITB3_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:11796
GenAtlas
THRA
GeneCards
THRA
GenBank Gene Database
X55074
GenBank Protein Database
825639
Guide to Pharmacology
588
UniProt Accession
THA_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:11799
GenAtlas
THRB
GeneCards
THRB
GenBank Gene Database
X04707
GenBank Protein Database
31207
Guide to Pharmacology
589
UniProt Accession
THB_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:12530
GeneCards
UGT1A1
GenBank Gene Database
M57899
GenBank Protein Database
184473
Guide to Pharmacology
2990
UniProt Accession
UD11_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:40
GenAtlas
ABCB1
GeneCards
ABCB1
GenBank Gene Database
M14758
GenBank Protein Database
307180
Guide to Pharmacology
768
UniProt Accession
MDR1_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:2622
GenAtlas
CYP2C8
GeneCards
CYP2C8
GenBank Gene Database
M17397
Guide to Pharmacology
1325
UniProt Accession
CP2C8_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:12405
GenAtlas
TTR
GeneCards
TTR
GenBank Gene Database
K02091
GenBank Protein Database
189582
Guide to Pharmacology
2851
UniProt Accession
TTHY_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:11583
GenAtlas
SERPINA7
GeneCards
SERPINA7
GenBank Gene Database
M14091
GenBank Protein Database
338697
UniProt Accession
THBG_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:399
GenAtlas
ALB
GeneCards
ALB
GenBank Gene Database
V00494
GenBank Protein Database
28590
UniProt Accession
ALBU_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:13819
GeneCards
SLCO1C1
GenBank Gene Database
AF260704
GenBank Protein Database
7839587
UniProt Accession
SO1C1_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:10923
GenAtlas
SLC16A2
GeneCards
SLC16A2
GenBank Gene Database
U05321
GenBank Protein Database
458255
UniProt Accession
MOT8_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:40
GenAtlas
ABCB1
GeneCards
ABCB1
GenBank Gene Database
M14758
GenBank Protein Database
307180
Guide to Pharmacology
768
UniProt Accession
MDR1_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:10956
GeneCards
SLCO1A2
GenBank Gene Database
U21943
GenBank Protein Database
885978
Guide to Pharmacology
1219
UniProt Accession
SO1A2_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:10959
GenAtlas
SLCO1B1
GeneCards
SLCO1B1
GenBank Gene Database
AF060500
GenBank Protein Database
5051630
Guide to Pharmacology
1220
UniProt Accession
SO1B1_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:10953
GeneCards
SLCO4A1
GenBank Gene Database
AB031051
GenBank Protein Database
6683743
UniProt Accession
SO4A1_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:11063
GenAtlas
SLC7A5
GeneCards
SLC7A5
GenBank Gene Database
AF077866
GenBank Protein Database
3639058
UniProt Accession
LAT1_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:10962
GenAtlas
SLCO2B1
GeneCards
SLCO2B1
GenBank Gene Database
AB026256
GenBank Protein Database
5006263
Guide to Pharmacology
1224
UniProt Accession
SO2B1_HUMAN
International reference pricing
103 formulations
Reference pricing from DrugBank. Prices are indicative and may not reflect current UK costs.
From $0.03/tablet
To $159.12/g
Eltroxin 0.05 mg Tablet
$0.03/tablet
Eltroxin 0.1 mg Tablet
$0.04/tablet
Eltroxin 0.15 mg Tablet
$0.04/tablet
Eltroxin 0.2 mg Tablet
$0.05/tablet
Synthroid 0.05 mg Tablet
$0.06/tablet
Source: DrugBank. Used under CC BY-NC 4.0 academic licence for non-commercial purposes.
Patent information
14 active patents, 6 expired
11241382
United States
Approved 8 Feb 2022 · Expires 17 Sept 2039
13y 5m
10231931
United States
Approved 19 Mar 2019 · Expires 23 Mar 2038
11y 11m
10406108
United States
Approved 10 Sept 2019 · Expires 23 Mar 2038
11y 11m
10537538
United States
Approved 21 Jan 2020 · Expires 28 Feb 2037
10y 11m
11096913
United States
Approved 24 Aug 2021 · Expires 28 Feb 2037
10y 11m
Source: DrugBank · CC BY-NC 4.0. Patent data sourced from national patent offices. Expiry dates may not reflect extensions, regulatory exclusivity periods, or legal challenges.
DrugBank citations
If you use DrugBank data in your research, please cite the following publications:
Knox C., Wilson M., Klinger C.M., et al
DrugBank 6.
0: the DrugBank Knowledgebase for 2024
Nucleic Acids Res. 2024 Jan 552(D1):D1265-D1275
Wishart D.S., Feunang Y.D., Guo A.C., et al
DrugBank 5.
0: a major update to the DrugBank database for 2018
Nucleic Acids Res. 2017 Nov 846(D1):D1074-D1082
Show earlier publications
Law V., Knox C., Djoumbou Y., et al
DrugBank 4.
0: shedding new light on drug metabolism
Nucleic Acids Res. 2014 Jan 142(1):D1091-7
Knox C., Law V., Jewison T., et al
DrugBank 3.
0: a comprehensive resource for 'omics' research on drugs
Nucleic Acids Res. 2011 Jan39(Database issue):D1035-41
Wishart D.S., Knox C., Guo A.C., et al
DrugBank: a knowledgebase for drugs, drug actions and drug targets.
Nucleic Acids Research
2008 Jan36(Database issue):D901-6
Wishart D.S., Knox C., Guo A.C., et al
DrugBank: a comprehensive resource for in silico drug discovery and exploration.
Nucleic Acids Research
2006 Jan 134(Database issue):D668-72
Source: go.drugbank.comCC BY-NC 4.0
Updated 27 days ago(8 Mar 2026)