The Acute Effect of Calcium Carbonate on the Intestinal Absorption of Levothyroxine
Abstract
To determine the acute effect of calcium, we measured levothyroxine absorption after ingestion of thyroxine (T4) with and without simultaneous ingestion of calcium (as calcium carbonate) in seven volunteers without thyroid disease. Serum total T4, total triiodothyronine (T3), free T4, and thyrotropin (TSH) levels were measured after ingestion of 1,000 microg of levothyroxine on two separate visits at 4-week intervals: (1) levothyroxine alone and (2) levothyroxine together with 2.0 g of calcium as calcium carbonate. The amount of absorbed levothyroxine was calculated as the incremental rise in serum T4 level during the first 6 hours multiplied by the volume of distribution for the hormone. When 1,000 microg of levothyroxine alone was given to subjects, the maximum average total T4 absorption was 837 microg (83.7% of the dose ingested) at 120 minutes. When levothyroxine was coadministered with 2.0 g of calcium (as calcium carbonate), the maximum average T4 absorption decreased to 579 microg (57.9% of the dose ingested) at 240 minutes. The total levothyroxine absorption over 6 hours was significantly greater with thyroxine than that with thyroxine and calcium (p = 0.02). The administration of calcium and levothyroxine in these subjects was associated with a significant reduction in the peak increment in serum total T4 (p = 0.02) and free T4 levels (p = 0.03), as well as a significant reduction in the overall increment in serum total T4 (p = 0.003), free T4 (p = 0.002), and total T3 levels (p = 0.01) over four time points (120 minutes, 240 minutes, 360 minutes, 1,440 minutes). In summary, this pharmacokinetic study in seven volunteers indicates that calcium carbonate acutely reduces T4 absorption.
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The list of medications that can alter the absorption of LT4 is extensive and includes calcium carbonate, PPIs, bile acid sequestrants (cholestyramine and colesevelam), phosphate binders, ferrous sulfate, aluminum-containing antacids, and sucralfate.
“The list of medications that can alter the absorption of LT4 is extensive and includes calcium carbonate (132-134), PPIs (135), bile acid sequestrants (cholestyramine and colesevelam) (136,137), phosphate binders (138,139), ferrous sulfate (140,141), aluminum-containing antacids (142,143), and sucralfate (144,145).”
From Guidelines for the Treatment of Hypothyroidism: Prepared by the American Thyroid Association Task Force on Thyroid Hormone Replacement (2014) · cites this paper as [133]
A subsequent absorption study showed that both Cmax and AUC were reduced when calcium carbonate and LT4 were co-administered (133).
“A subsequent absorption study showed that both the Cmax and AUC were reduced when calcium carbonate and LT4 were co-administered (133).”
From Guidelines for the Treatment of Hypothyroidism: Prepared by the American Thyroid Association Task Force on Thyroid Hormone Replacement (2014) · cites this paper as [133]
Calcium carbonate adsorbed T4 dose-dependently at pH 2 but not pH 7.4, thus explaining L-T4 malabsorption, and reduced T4 pharmacokinetics.
“Calcium carbonate adsorbed T4 dose-dependently at pH 2 but not pH 7.4, thus explaining L-T4 malabsorption (41), and reduced T4 pharmacokinetics (42).”
From L-T4 therapy in the presence of pharmacological interferents (2020) · cites this paper as [42]
Cites
Surks, M. I., & Sievert, R. (1995) · New England Journal of Medicine · doi:10.1056/nejm199512213332507 · Cited by 349 · see citing works
Levothyroxine Therapy in Patients with Thyroid Disease
Mandel, S. J., Brent, G. A., & Larsen, P. R. (1993) · Annals of Internal Medicine · doi:10.7326/0003-4819-119-6-199309150-00009 · Cited by 324 · see citing works
Ferrous sulfate reduces thyroxine efficacy in patients with hypothyroidism
Campbell, N. R. C., Hasinoff, B. B., Stalts, H., Rao, B., & Wong, N. C. W. (1992) · Annals of Internal Medicine · doi:10.7326/0003-4819-117-12-1010 · Cited by 231 · see citing works
Effect of calcium carbonate on the absorption of levothyroxine
Singh, N. (2000) · JAMA · doi:10.1001/jama.283.21.2822 · Cited by 219 · see citing works
Self-citationSimultaneous Measurement of Thyroxine and Triiodothyronine Peripheral Turnover Kinetics in Man
Nicoloff, J. T., LOW, J. C., Dussault, J. H., & Fisher, D. A. (1972) · Journal of Clinical Investigation · doi:10.1172/jci106835 · Cited by 217 · see citing works
Delayed Intestinal Absorption of Levothyroxine
BENVENGA, S., BARTOLONE, L., SQUADRITO, S., GIUDICE, F. L., & TRIMARCHI, F. (1995) · Thyroid · doi:10.1089/thy.1995.5.249 · Cited by 156 · see citing works
The influence of cholestyramine on thyroxine absorption
Northcutt, R. C. (1969) · JAMA: The Journal of the American Medical Association · doi:10.1001/jama.1969.03160100047012 · Cited by 144 · see citing works
Localization of human thyroxine absorption
HAYS, M. T. (1991) · Thyroid · doi:10.1089/thy.1991.1.241 · Cited by 138 · see citing works
Liel, Y., Harman-Boehm, I., & Shany, S. (1996) · The Journal of Clinical Endocrinology & Metabolism · doi:10.1210/jcem.81.2.8636317 · Cited by 129 · see citing works
Absorption of oral thyroxine in man
HAYS, M. T. (1968) · The Journal of Clinical Endocrinology & Metabolism · doi:10.1210/jcem-28-6-749 · Cited by 111 · see citing works
Sucralfate causes malabsorption of L-thyroxine
Sherman, S. I., Tielens, E. T., & Ladenson, P. W. (1994) · The American Journal of Medicine · doi:10.1016/0002-9343(94)90093-0 · Cited by 105 · see citing works
Kung, A. W. C., & Yeung, S. S. (1996) · The Journal of Clinical Endocrinology & Metabolism · doi:10.1210/jcem.81.3.8772604 · Cited by 100 · see citing works
Pseudomalabsorption of levothyroxine
Ain, K. B. (1991) · JAMA: The Journal of the American Medical Association · doi:10.1001/jama.1991.03470150090036 · Cited by 100 · see citing works
Nonspecific intestinal adsorption of levothyroxine by aluminum hydroxide
Liel, Y., Sperber, A. D., & Shany, S. (1994) · The American Journal of Medicine · doi:10.1016/0002-9343(94)90303-4 · Cited by 83 · see citing works
Human Thyroxine Absorption: Age Effects and Methodological Analyses
HAYS, M. T., & NIELSEN, K. R. K. (1994) · Thyroid · doi:10.1089/thy.1994.4.55 · Cited by 67 · see citing works
Sperber, A. D. (1992) · Archives of Internal Medicine · doi:10.1001/archinte.1992.00400130181024 · Cited by 66 · see citing works
Elevated serum thyrotropin in thyroxine-treated patients with hypothyroidism given sertraline
(1997) · New England Journal of Medicine · doi:10.1056/nejm199710023371415 · Cited by 60 · see citing works
Absorption fo Oral Thyroxine in Hypothyroid and Normal Man
READ, D. G., Hays, M. T., & Hershman, J. M. (1970) · The Journal of Clinical Endocrinology & Metabolism · doi:10.1210/jcem-30-6-798 · Cited by 58 · see citing works
Self-citationMOHAMED SHAKIR, K. M., CHUTE, J. P., APRILL, B. S., & LAZARUS, A. A. (1997) · Southern Medical Journal · doi:10.1097/00007611-199706000-00011 · Cited by 55 · see citing works
Levothyroxine Binding by Sucralfate
Havránková, J., & Lahaie, R. G. (1992) · Annals of Internal Medicine · doi:10.7326/0003-4819-117-5-445_3 · Cited by 41 · see citing works
Effects of Pharmacological Fiber Supplements on Levothyroxine Absorption
Chiu, A. C., & Sherman, S. I. (1998) · Thyroid® · doi:10.1089/thy.1998.8.667 · Cited by 41 · see citing works
Calcium Carbonate and Reduction of Levothyroxine Efficacy
Schneyer, C. R. (1998) · JAMA · doi:10.1001/jama.279.10.750-b · Cited by 35 · see citing works
Pseudomalabsorption of levothyroxine
Ain, K. B. (1991) · JAMA · doi:10.1001/jama.266.15.2118 · Cited by 28 · see citing works
Flagged first, then by citations
Cited by
Sorted by citations
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., et al. (2014) · Thyroid® · doi:10.1089/thy.2014.0028 · Cited by 1,928 · see citing works
“A subsequent absorption study showed that both the Cmax and AUC were reduced when calcium carbonate and LT4 were co-administered (133).”
Conditions and drugs interfering with thyroxine absorption
Liwanpo, L., & Hershman, J. M. (2009) · Best Practice & Research Clinical Endocrinology & Metabolism · doi:10.1016/j.beem.2009.06.006 · Cited by 222 · see citing works
Self-citationA review of the pharmacokinetics of levothyroxine for the treatment of hypothyroidism
Colucci, P., Yue, C. S., Ducharme, M., Benvenga, S., Principal Scientist, L. A. C. I., Principal Scientist, L. A. C. I. A. P. C., President and CEO, L. A. C. I., & Professor of Medicine, D. (2010) · European Endocrinology · doi:10.17925/ee.2013.09.01.40 · Cited by 167 · see citing works
Gastrointestinal malabsorption of thyroxine
Virili, C., Antonelli, A., Santaguida, M. G., Benvenga, S., & Centanni, M. (2019) · Endocrine Reviews · doi:10.1210/er.2018-00168 · Cited by 164 · see citing works
Factors Affecting Gastrointestinal Absorption of Levothyroxine: A Review
Skelin, M., Lucijanić, T., Amidžić Klarić, D., Rešić, A., Bakula, M., Liberati-Čizmek, A.-M., Gharib, H., & Rahelić, D. (2017) · Clinical Therapeutics · doi:10.1016/j.clinthera.2017.01.005 · Cited by 133 · see citing works
Hypothyroidism in the Elderly: Pathophysiology, Diagnosis and Treatment
Laurberg, P., Andersen, S., Pedersen, I. B., & Carl, A. B. (2005) · Drugs & Aging · doi:10.2165/00002512-200522010-00002 · Cited by 141 · see citing works
Diagnosis and management of treatment-refractory hypothyroidism: an expert consensus report
Centanni, M., Benvenga, S., & Sachmechi, I. (2017) · Journal of Endocrinological Investigation · doi:10.1007/s40618-017-0706-y · Cited by 113 · see citing works
“As noted above, a large and growing number of medications, supplements, and food items have been shown to alter the fraction of an ingested dose that is absorbed [109, 110].”
BackgroundLevothyroxine Dose Adjustment to Optimise Therapy Throughout a Patient’s Lifetime
Duntas, L. H., & Jonklaas, J. (2019) · Advances in Therapy · doi:10.1007/s12325-019-01078-2 · Cited by 94 · see citing works
Levothyroxine Replacement Doses Are Affected by Gender and Weight, But Not Age
Devdhar, M., Drooger, R., Pehlivanova, M., Singh, G., & Jonklaas, J. (2011) · Thyroid · doi:10.1089/thy.2011.0029 · Cited by 90 · see citing works
Levothyroxine interactions with food and dietary supplements – a systematic review
Wiesner, A., Gajewska, D., & Paśko, P. (2021) · Pharmaceuticals · doi:10.3390/ph14030206 · Cited by 85 · see citing works
“• low level of evidence: most studies are single case reports, case series, cohort studies (mainly retrospective), clinical studies without control groups (see Figure 1 and Table 2); • small number of patients in experimental studies: ≤10 participants [36,50,59,61,62,64, 75,79,80,85,87,98]; • presence of older studies…”
BackgroundResultNew medications which decrease levothyroxine absorption
John-Kalarickal, J., Pearlman, G., & Carlson, H. E. (2007) · Thyroid · doi:10.1089/thy.2007.0060 · Cited by 82 · see citing works
Absorption of Levothyroxine When Coadministered with Various Calcium Formulations
Zamfirescu, I., & Carlson, H. E. (2011) · Thyroid · doi:10.1089/thy.2010.0296 · Cited by 76 · see citing works
Pirola, I., Formenti, A. M., Gandossi, E., Mittempergher, F., Casella, C., Agosti, B., & Cappelli, C. (2013) · Obesity Surgery · doi:10.1007/s11695-013-1015-y · Cited by 74 · see citing works
Sex and Age Differences in Levothyroxine Dosage Requirement
Jonklaas, J. (2010) · Endocrine Practice · doi:10.4158/ep09257.or · Cited by 72 · see citing works
Morris, J. C. (2009) · Clinical Endocrinology · doi:10.1111/j.1365-2265.2009.03536.x · Cited by 59 · see citing works
Rubio, I. G. S., Galrão, A. L., Santo, M. A., Zanini, A. C., & Medeiros-Neto, G. (2012) · Obesity Surgery · doi:10.1007/s11695-011-0452-8 · Cited by 58 · see citing works
Guglielmi, R., Grimaldi, F., Negro, R., Frasoldati, A., Misischi, I., Graziano, F., Cipri, C., Guastamacchia, E., Triggiani, V., & Papini, E. (2018) · Endocrine, Metabolic & Immune Disorders - Drug Targets · doi:10.2174/1871530318666180125155348 · Cited by 57 · see citing works
Spaggiari, G., Brigante, G., Vincentis, S. D., Cattini, U., Roli, L., Santis, M. C. D., Baraldi, E., Tagliavini, S., Varani, M., Trenti, T., et al. (2017) · Frontiers in Endocrinology · doi:10.3389/fendo.2017.00316 · Cited by 55 · see citing works
Ward, L. S. (2010) · Arquivos Brasileiros de Endocrinologia & Metabologia · doi:10.1590/s0004-27302010000500002 · Cited by 53 · see citing works
Di Donna, V., Santoro, M. G., de Waure, C., Ricciato, M. P., Paragliola, R. M., Pontecorvi, A., & Corsello, S. M. (2014) · Thyroid · doi:10.1089/thy.2014.0111 · Cited by 52 · see citing works
Herbal, Prescribed, and Over-the-Counter Drug Use in Older Women: Prevalence of Drug Interactions
Yoon, S. L., & Schaffer, S. D. (2006) · Geriatric Nursing · doi:10.1016/j.gerinurse.2006.02.014 · Cited by 46 · see citing works
Brancato, D., Scorsone, A., Saura, G., Ferrara, L., Di Noto, A., Aiello, V., Fleres, M., & Provenzano, V. (2014) · Endocrine Practice · doi:10.4158/ep13418.or · Cited by 44 · see citing works
Trifirò, G., Parrino, F., Sultana, J., Giorgianni, F., Ferrajolo, C., Bianchini, E., Medea, G., Benvenga, S., Cricelli, I., Cricelli, C., et al. (2015) · Clinical Drug Investigation · doi:10.1007/s40261-015-0271-0 · Cited by 40 · see citing works
Nonthyroidal illness and the cardiorenal syndrome
Meuwese, C. L., Dekkers, O. M., Stenvinkel, P., Dekker, F. W., & Carrero, J. J. (2013) · Nature Reviews Nephrology · doi:10.1038/nrneph.2013.170 · Cited by 39 · see citing works
The Effect of Famotidine, Esomeprazole, and Ezetimibe on Levothyroxine Absorption
Ananthakrishnan, S., Braverman, L. E., Levin, R. M., Magnani, B., & Pearce, E. N. (2008) · Thyroid · doi:10.1089/thy.2007.0381 · Cited by 38 · see citing works
Colesevelam hydrochloride and lanthanum carbonate interfere with the absorption of levothyroxine
Weitzman, S. P., Ginsburg, K. C., & Carlson, H. E. (2009) · Thyroid · doi:10.1089/thy.2008.0312 · Cited by 35 · see citing works
Concurrent milk ingestion decreases absorption of levothyroxine
Chon, D. A., Reisman, T., Weinreb, J. E., Hershman, J. M., & Leung, A. M. (2018) · Thyroid · doi:10.1089/thy.2017.0428 · Cited by 34 · see citing works
Self-citationSelf-Medication Practices of Spanish-Speaking Older Adults in Hartford, Connecticut
Neafsey, P. J., Jarrin, O. F., Luciano, S., & Coffman, M. J. (2007) · Hispanic Health Care International · doi:10.1891/154041507783095795 · Cited by 30 · see citing works
Medications and Food Interfering with the Bioavailability of Levothyroxine: A Systematic Review
Liu, H., Lu, M., Hu, J., Fu, G., Feng, Q., Sun, S., & Chen, C. (2023) · Therapeutics and Clinical Risk Management · doi:10.2147/tcrm.s414460 · Cited by 29 · see citing works
The clinical utility of free thyroxine in oral levothyroxine absorption testing
Ching Sun, G. E., Pantalone, K. M., Faiman, C., Gupta, M., Olansky, L., & Hatipoglu, B. (2014) · Endocrine Practice · doi:10.4158/ep13487.or · Cited by 27 · see citing works
Interaction between levothyroxine and calcium carbonate.
Mazokopakis, E. E., Giannakopoulos, T. G., & Starakis, I. (2008) · PubMed Central · Cited by 22 · see citing works
Calcium Homeostasis in Thyroid Disease in Dogs and Cats
Schenck, P. A. (2007) · Veterinary Clinics of North America Small Animal Practice · doi:10.1016/j.cvsm.2007.03.007 · Cited by 17 · see citing works
Drug–Drug Interactions With Over-The-Counter Medicines: Mind the Unprescribed
Scherf‐Clavel, O. (2021) · Therapeutic Drug Monitoring · doi:10.1097/ftd.0000000000000924 · Cited by 17 · see citing works
Interference with the absorption of levothyroxine
Singh, N. K., & Hershman, J. M. (2003) · Current Opinion in Endocrinology & Diabetes · doi:10.1097/00060793-200310000-00008 · Cited by 15 · see citing works
Self-citationMetformin does not suppress serum thyrotropin by increasing levothyroxine absorption
Al-Alusi, M. A., Du, L., Li, N., Yeh, M. W., He, X., Braverman, L. E., & Leung, A. M. (2015) · Thyroid · doi:10.1089/thy.2015.0211 · Cited by 14 · see citing works
Levothyroxine pseudo-malabsorption: testing and treatment in the outpatient setting
Rdzak, G. M., Whitman, L. M., & Inzucchi, S. E. (2018) · Therapeutic Advances in Endocrinology and Metabolism · doi:10.1177/2042018818771433 · Cited by 14 · see citing works
Cataldo, E., Columbano, V., Nielsen, L., Gendrot, L., Covella, B., & Piccoli, G. B. (2018) · BMC Nephrology · doi:10.1186/s12882-018-0947-9 · Cited by 14 · see citing works
L-T4 therapy in the presence of pharmacological interferents
Benvenga, S. (2020) · Frontiers in Endocrinology · doi:10.3389/fendo.2020.607446 · Cited by 13 · see citing works
“4, thus explaining L-T4 malabsorption (41), and reduced T4 pharmacokinetics (42).”
BackgroundWelder, G. J., Wessel, T. R., Arant, C. B., Schofield, R. S., & Zineh, I. (2006) · Pharmacotherapy The Journal of Human Pharmacology and Drug Therapy · doi:10.1592/phco.26.12.1794 · Cited by 12 · see citing works
Pseudomalabsorption de L-thyroxine: une forme de pathomimie
Molines, L., Fromont, I., Morlet-Barla, N., Nogueira, J.-P., Valéro, R., & Vialettes, B. (2007) · La Presse Médicale · doi:10.1016/j.lpm.2006.09.024 · Cited by 10 · see citing works
Hypothyroïdie secondaire à une interaction médicamenteuse entre lévothyroxine et sels de fer
Fiaux, E., Kadri, K., Levasseur, C., Guillou, C. L., & Chassagne, P. (2010) · La Revue de Médecine Interne · doi:10.1016/j.revmed.2009.09.038 · Cited by 10 · see citing works
Thyroid Nodules and Cancer in the Elderly
Lechner, M. G., & Hershman, J. M. (2015) · Cited by 10 · see citing works
Self-citationHeim, M., Nixon, I. J., Emmerson, E., & Callanan, A. (2022) · Frontiers in Endocrinology · doi:10.3389/fendo.2022.997288 · Cited by 10 · see citing works
Levothyroxine and Calcium Interaction Timing Is Everything
Neafsey, P. J. (2004) · Home Healthcare Now · doi:10.1097/00004045-200405000-00015 · Cited by 9 · see citing works
Hypothyroidism: current diagnostic and treatment principles
Моргунова, Т. Б., & Fadeev, V. V. (2016) · Meditsinskiy sovet = Medical Council · doi:10.21518/2079-701x-2016-3-79-81 · Cited by 8 · see citing works
Hypothyroidism in Older Adults
Kim, M. I. (2000) · Cited by 8 · see citing works
Weiss, R. E., & Refetoff, S. (2015) · Elsevier eBooks · doi:10.1016/b978-0-323-18907-1.00078-0 · Cited by 8 · see citing works
Levothyroxine intramuscular administration-Case report and Review of literature
Mikhail, N. E. (2020) · Clinical Research and Trials · doi:10.15761/crt.1000291 · Cited by 6 · see citing works
Self Medication Practices among Patients taking Levothyroxine
(2004) · The Internet Journal of Advanced Nursing Practice · doi:10.5580/22a8 · Cited by 6 · see citing works
Cherchir, F., Oueslati, I., Mouelhi, Y., Talbi, E., Feki, M., Yazidi, M., & Chihaoui, M. (2023) · SAGE Open Medical Case Reports · doi:10.1177/2050313x231209229 · Cited by 5 · see citing works
Treatment of Thyroxine Malabsorption
Kempke, J., Hussain, H., Bhan, B., & Graves, L. (2015) · Journal of Endocrinology and Metabolism · doi:10.14740/jem277w · Cited by 5 · see citing works
Oueslati, I., Terzi, A., Yazidi, M., Kamoun, E., Feki, M., & Chihaoui, M. (2025) · Endocrine · doi:10.1007/s12020-025-04312-w · Cited by 3 · see citing works
Environmental factors as a reason of thyroid gland pathology (analytical review, the first report)
Antonenko, A. M., & Korshun, M. M. (2016) · Environment & Health · doi:10.32402/dovkil2016.03.074 · Cited by 3 · see citing works
Dalugodage, S. S., Bowatte, G., Antonypillai, C., Rajapakse, S., & Tennakoon, T. M. I. U. K. (2024) · BMC Medical Genomics · doi:10.1186/s12920-024-01849-z · Cited by 2 · see citing works
Hanmayyagari, B. (2020) · IAR Journal of Medicine and Surgery Research · doi:10.47310/iarjmsr.2020.v01i01.07 · Cited by 2 · see citing works
Weiss, R. E., & Refetoff, S. (2010) · Elsevier eBooks · doi:10.1016/b978-1-4160-5583-9.00077-0 · Cited by 2 · see citing works
Thyroid and food: a Mediterranean perspective
Tubili, C., Morviducci, L., Nardone, M. R., Tubili, F., Falco, D. D., & Folco, U. D. (2012) · Mediterranean Journal of Nutrition and Metabolism · doi:10.1007/s12349-012-0095-x · Cited by 2 · see citing works
Relationship Between Thyroid Hormones and Left Ventricular Mass in Peritoneal Dialysis Patients.
Mehdiabadi, F. M., Rashidinejad, A., Mahdavi, A., & Dehesh, T. (2020) · PubMed · doi:10.5254/ijkd.5158 · Cited by 2 · see citing works
Ali, D. S., Perrier, N. D., & Khan, A. A. (2026) · Thyroid · doi:10.1177/10507256261454145 · Cited by 1 · see citing works
Ergin, A. B., Hamrahian, A. H., Kennedy, A. L., & Gupta, M. K. (2015) · Springer eBooks · doi:10.1007/978-3-319-13048-4_22 · Cited by 1 · see citing works
Importance of Thyroid Hormone Replacement Therapy in Patients with Medullary Thyroid Cancer
Jonklaas, J. (2016) · Springer eBooks · doi:10.1007/978-3-319-39412-1_13 · Cited by 1 · see citing works
Influence of Drugs on Thyroid Function Tests
Ananthakrishnan, S., & Pearce, E. N. (2010) · Endocrine updates · doi:10.1007/978-1-4419-1485-9_13 · Cited by 1 · see citing works
Campanini, M., & Grandi, M. (2017) · Italian Journal of Medicine · doi:10.4081/itjm.q.2017.3 · Cited by 1 · see citing works
Hariman, C., Pelluri, L., & O'Weickert, M. (2014) · Endocrine Abstracts · doi:10.1530/endoabs.34.p384
Thyroid Hormone Treatment for Differentiated Thyroid Carcinoma: What Drug, How Long, What Dose?
Piantanida, E., Compri, E., Gandolfo, M., Sassi, L., Dionigi, G., Lai, A., Tanda, M. L., & Bartalena, L. (2009) · Current Cancer Therapy Reviews · doi:10.2174/157339409789712717
Alternative Delivery Approaches for Levothyroxine (T4)
Anand, U., Agu, R. U., & Imran, S. A. (2013) · Canadian Journal of Diabetes · doi:10.1016/j.jcjd.2013.08.074
Predicting Interactions between Medicinal Drugs and New Supplements
Kubota, T., YOSHIOKA, S. R. I., KAWAGOE, N., Toyoda, T., ISHIBASHI, N., & Suzuki, N. (2010) · Japanese Journal of Complementary and Alternative Medicine · doi:10.1625/jcam.7.67
Má absorção das hormonas tiroideias.
Nobre, E. L., Jorge, Z., Anselmo, J., Lopes, C., César, R., Santos, V., & de Castro, J. J. (2004) · DOAJ (DOAJ: Directory of Open Access Journals) · doi:10.20344/amp.1116
Cohen, R. (2008) · Elsevier eBooks · doi:10.1016/b978-1-4160-4745-2.00023-7
Luíz, H. V., Manita, I., & Portugal, J. (2016) · Springer eBooks · doi:10.1007/978-3-319-25871-3_7
Deprescribing in Patients of Hypothyroidism Results in Better Health Outcome: A Case Series
Mishra, P., & Bhargava, S. (2023) · Journal of Pharmaceutical Care · doi:10.18502/jpc.v10i4.11589
GÖKEŞ, D., & Arslan, M. (2024) · Ankara Universitesi Eczacilik Fakultesi Dergisi · doi:10.33483/jfpau.1432068
Hanmayyagari, B. (2020) · IAR Journal of Medicine and Surgery Research · doi:10.47310/iarjmsr.2020.v01i01.06
Agrawal, N., Roy, A., Chakraborty, P. P., & Bhattacharjee, R. (2026) · JCEM Case Reports · doi:10.1210/jcemcr/luag084
Abdel-Salam, E. T., Salam, M. A. E., Anwar, Z. M., Mostafa, H. M., Ibrahim, A. Z., Elsalam, M., & El‐Magid, M. A. (2026) · Luminescence · doi:10.1002/bio.70625
- Authors
- Singh, N., Weisler, S. L., & Hershman, J. M.
- Affiliations
- VA Greater Los Angeles Healthcare System (US)
- Venue
- Thyroid
- Publisher
- SAGE Publications
- Published
- 2001-10
- Volume
- 11
- Issue
- 10
- Pages
- 967-971
- ISSN
- 1050-7256 (ISSN-L)
- 1557-9077
- OpenAlex
- W2168410270
- Cited by
- 77
- References
- 22
- Citations by year
- 2026: 3 · 2025: 1 · 2024: 2 · 2023: 3 · 2022: 1 · 2021: 2 · 2020: 5 · 2019: 1 · 2018: 5 · 2017: 4 · 2016: 5 · 2015: 6 · 2014: 5 · 2013: 3 · 2012: 1
- FWCI
- 0.92
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Thyroid (publishedVersion)
- PubMed (publishedVersion)
- Funders
- Abbott Laboratories
- Topics
- Health Sciences › Medicine › Endocrinology, Diabetes and Metabolism › Thyroid Disorders and Treatments
- Life Sciences › Pharmacology, Toxicology and Pharmaceutics › Pharmaceutical Science › Drug Solubulity and Delivery Systems
- Health Sciences › Medicine › Surgery › Thyroid and Parathyroid Surgery
- Keywords
- levothyroxine, calcium carbonate, intestinal absorption, drug-drug interactions, thyroid hormone absorption, serum thyroxine, triiodothyronine, thyroid-stimulating hormone, free thyroxine
- MeSH terms
- Adult, Calcium Carbonate, Female, Humans, Intestinal Absorption, Male, Thyrotropin, Thyroxine, Triiodothyronine
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
Statistics and arithmetic are recomputed, not judged.
Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.
What counts as a claim ›How we measure confidence ›How we check this ›
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