{
  "schemaVersion": 2,
  "eyebrow": "Endocrinology",
  "title": "Hyperthyroidism",
  "summary": "Confirm biochemical thyrotoxicosis, rapidly identify thyroid storm, then distinguish hormone overproduction from destructive or exogenous hormone exposure to select thionamides, definitive therapy, or non-antithyroid management.",
  "seoDescription": "Physician approach to hyperthyroidism: biochemical confirmation, etiologic testing, thyroid storm treatment, thionamide safety, and definitive therapy selection.",
  "clinicalQuestion": "How should physicians confirm, classify, stabilize, and treat hyperthyroidism and other causes of thyrotoxicosis?",
  "specialty": "Endocrinology",
  "audience": "U.S. physicians and medical trainees",
  "tags": [
    "hyperthyroidism",
    "thyrotoxicosis",
    "Graves disease",
    "thyroid storm",
    "methimazole",
    "propylthiouracil",
    "radioiodine uptake"
  ],
  "keyTakeaways": [
    "A low TSH with elevated free T4 or free T4 index establishes biochemical hyperthyroidism; obtain T3 when TSH is low and free T4 is normal to identify T3 thyrotoxicosis. [7][12][13]",
    "Separate increased hormone synthesis from thyroiditis or exogenous hormone exposure before prescribing a thionamide: uptake imaging, TRAb/TSI, Doppler ultrasound, goiter, and thyroglobulin provide the key branch points. [5][7][9][13]",
    "Treat suspected thyroid storm immediately with supportive care, beta-blockade, a thionamide, then iodine at least 1 hour later; PTU 500-1,000 mg loading followed by 250 mg every 4 hours is one established regimen. [17][23]",
    "Methimazole is generally preferred for nonpregnant hyperthyroidism because PTU carries serious hepatotoxicity risk; reserve PTU for the first trimester of pregnancy, methimazole intolerance, or selected thyroid-storm regimens. [18][19][21]",
    "Radioiodine and thyroidectomy are definitive options for hormone-overproducing disease; radioiodine can transiently worsen thyrotoxicosis and may worsen Graves orbitopathy, particularly in smokers. [10][16]"
  ],
  "sections": [
    {
      "id": "urgent-triage",
      "eyebrow": "First decision",
      "heading": "Identify thyroid storm and stabilize before etiologic testing",
      "intro": "Rapid deterioration in thyrotoxicosis requires intensive treatment rather than outpatient diagnostic sequencing.",
      "paragraphs": [
        "Treat severe thyrotoxicosis with rapid clinical deterioration as suspected thyroid storm. Initiate cardiovascular stabilization, respiratory support as needed, temperature control, and evaluation and treatment of precipitating factors while beginning thyroid-directed therapy. [22]",
        "After initial supportive measures, start propranolol 40-80 mg orally every 4-6 hours in suspected thyroid storm unless beta-blockade is clinically unsuitable. Give PTU 500-1,000 mg as a loading dose followed by 250 mg every 4 hours, or methimazole 20 mg every 4-6 hours; PTU additionally inhibits peripheral T4-to-T3 conversion. [23]",
        "Administer iodine only after thionamide therapy: give supersaturated potassium iodide 5 drops orally every 6 hours beginning 1 hour after PTU or methimazole. This sequence avoids providing substrate for new thyroid hormone synthesis before synthesis blockade. [23]"
      ],
      "bullets": [
        "Use oral, nasogastric, or rectal PTU when enteral delivery is necessary; a total PTU dose of 1,200-1,500 mg/day is described for thyroid storm. [18]",
        "Use glucocorticoids as part of thyroid-storm pharmacotherapy to reduce peripheral hormone conversion and support adrenal function. [22]",
        "For refractory severe disease or contraindications to thionamides, therapeutic plasma exchange can be a bridge to radioiodine or thyroidectomy; reported series describe four to six exchanges on average, with daily free T3 and free T4 monitoring. [17]",
        "Do not plan thyroidectomy before medical control in most thyroid-storm cases; surgery has been proposed when standard therapy fails to improve the patient within 12-24 hours. [22]"
      ],
      "subsections": [],
      "table": {
        "caption": "Immediate treatment sequence for suspected thyroid storm. [22][23]",
        "columns": [
          "Step",
          "Action",
          "Timing or dose"
        ],
        "rows": [
          [
            "1",
            "Support circulation, respiration, and temperature; identify and treat precipitant. [22]",
            "Immediately. [22]"
          ],
          [
            "2",
            "Start propranolol. [23]",
            "40-80 mg orally every 4-6 hours. [23]"
          ],
          [
            "3",
            "Block synthesis with PTU or methimazole. [23]",
            "PTU 500-1,000 mg load, then 250 mg every 4 hours; or methimazole 20 mg every 4-6 hours. [23]"
          ],
          [
            "4",
            "Block hormone release with SSKI. [23]",
            "5 drops orally every 6 hours, starting 1 hour after thionamide. [23]"
          ]
        ]
      }
    },
    {
      "id": "biochemical-confirmation",
      "eyebrow": "Laboratory branch",
      "heading": "Confirm the biochemical pattern before labeling the cause",
      "intro": "TSH establishes the screening branch; free T4 and T3 determine overt versus subclinical disease.",
      "paragraphs": [
        "Obtain serum TSH and free T4 (or free T4 index) when hyperthyroidism is suspected. A low TSH with elevated free T4 or free T4 index is the biochemical pattern of hyperthyroidism. TSH is typically less than 0.1 mU/L in overt primary hyperthyroidism and is often less than 0.02 mU/L. [6][12]",
        "If TSH is suppressed but free T4 is normal, obtain total T3 or free T3 to detect isolated T3 thyrotoxicosis. Elevated T3 with normal free T4 represents active overt disease; normal free T4 and T3 with low TSH represents subclinical hyperthyroidism. Free T3 measurement may be less reliable than total T3. [7][12][13]",
        "A low TSH is not always primary thyroid hormone excess. Low or normal TSH together with low free T4 indicates central hypothyroidism rather than hyperthyroidism. During the first trimester, hCG-mediated stimulation can lower TSH; assess overt disease with free T4 or pregnancy-specific total T4 reference ranges. [9][12]"
      ],
      "bullets": [
        "Review prescribed thyroid hormone, supplements, and iodine exposure before assigning endogenous disease; this can identify exogenous thyroid hormone use or iodine oversupplementation. [13]",
        "Use thyroid indices obtained close to the time of radionuclide testing because uptake interpretation depends on TSH being suppressed during the study. [7]"
      ],
      "subsections": [],
      "table": {
        "caption": "Biochemical patterns that redirect the diagnostic pathway. [6][7][9][12]",
        "columns": [
          "TSH",
          "Free T4 or FTI",
          "T3",
          "Interpretation and next action"
        ],
        "rows": [
          [
            "Low",
            "Elevated",
            "Usually elevated",
            "Overt hyperthyroidism; determine etiology. [6][12]"
          ],
          [
            "Low",
            "Normal",
            "Elevated",
            "T3 thyrotoxicosis; manage as overt hyperthyroidism and determine etiology. [7][12]"
          ],
          [
            "Low",
            "Normal",
            "Normal",
            "Subclinical hyperthyroidism; treatment is more controversial than for overt disease. [7]"
          ],
          [
            "Low or normal",
            "Low",
            "Not required for classification",
            "Consider central hypothyroidism, not primary hyperthyroidism. [12]"
          ]
        ]
      }
    },
    {
      "id": "etiologic-classification",
      "eyebrow": "Cause-directed testing",
      "heading": "Differentiate Graves disease, autonomous nodules, thyroiditis, and exogenous hormone",
      "intro": "The critical distinction is increased synthesis versus release or ingestion of preformed hormone.",
      "paragraphs": [
        "Increased radioiodine uptake identifies endogenous hormone overproduction and most often reflects Graves disease, toxic multinodular goiter, or toxic adenoma. Graves disease is the most common cause of hyperthyroidism, followed by toxic nodular goiter; thyroiditis is an important alternative cause of thyrotoxicosis. [1][5]",
        "Order TSH-receptor antibodies or thyroid-stimulating immunoglobulin when Graves disease is suspected or radionuclide imaging is unsuitable. Positive TRAb or TSI supports Graves disease; exophthalmos or extraocular muscle involvement further supports Graves orbitopathy. A thyroid uptake scan, TRAb/TSI measurement, and ultrasound are complementary tools for separating Graves disease, toxic multinodular goiter, and toxic adenoma. [9][13][14]",
        "Use radionuclide uptake/scan to distinguish hormone production from transient thyroiditis or factitious thyrotoxicosis when the clinical diagnosis is uncertain. Low uptake with absent goiter and low thyroglobulin favors exogenous thyroid hormone use. In contrast, high uptake points to Graves disease, toxic multinodular goiter, or toxic adenoma. [5][7][8]",
        "Avoid radioactive iodine diagnostic studies in pregnancy. In pregnancy, breastfeeding, or persons trying to conceive, thyroid ultrasound with Doppler blood flow can help distinguish Graves disease from thyroiditis; TRAb or TSI provides an additional non-radiation test. Measure TSI or TRAb at 20-24 weeks' gestation when Graves disease is present to determine the need for increased fetal monitoring. [9][10]"
      ],
      "bullets": [
        "Graves disease: diffuse autoimmune stimulation; positive TRAb/TSI and orbitopathy favor this branch. [9][14]",
        "Toxic multinodular goiter or toxic adenoma: high uptake hyperthyroidism from autonomous nodular disease; the scan helps separate these from Graves disease. [5][9]",
        "Thyroiditis: transient thyrotoxicosis with low uptake; antithyroid drugs do not address release of preformed hormone. [7][9]",
        "Factitious thyrotoxicosis: low uptake, absent goiter, and low thyroglobulin; investigate thyroid hormone access and use. [7][8]"
      ],
      "subsections": [],
      "table": {
        "caption": "Etiologic branch points in biochemically confirmed thyrotoxicosis. [5][7][8][9][13][14]",
        "columns": [
          "Etiology",
          "Discriminating findings",
          "Next action"
        ],
        "rows": [
          [
            "Graves disease",
            "TRAb/TSI positive; orbitopathy supports diagnosis; typically high uptake. [5][9][14]",
            "Use antithyroid therapy for active hormone synthesis; assess definitive-therapy options and orbitopathy implications. [4][10]"
          ],
          [
            "Toxic multinodular goiter or toxic adenoma",
            "High uptake hyperthyroidism; scan distinguishes autonomous nodular disease from Graves disease. [5][9]",
            "Select antithyroid control while considering radioiodine or surgery for definitive management. [10][24]"
          ],
          [
            "Thyroiditis",
            "Low uptake indicating transient release rather than overproduction. [7][9]",
            "Do not use thionamide solely to block synthesis; manage the thyrotoxic phase and reassess thyroid function. [7]"
          ],
          [
            "Exogenous thyroid hormone",
            "Low uptake, absent goiter, low thyroglobulin; antibodies usually absent without prior autoimmunity. [7][8]",
            "Stop or correct hormone exposure and consider supervised serial thyroid testing when covert use is suspected. [8]"
          ]
        ]
      }
    },
    {
      "id": "medical-treatment",
      "eyebrow": "Hormone overproduction",
      "heading": "Use symptom control and thionamides for Graves disease or autonomous hyperthyroidism",
      "intro": "Thionamides treat synthesis, not destructive thyroiditis or exogenous hormone exposure.",
      "paragraphs": [
        "For symptomatic relief of adrenergic manifestations while definitive biochemical control is pending, use a beta-blocker such as propranolol or atenolol. These agents reduce palpitations, tachycardia, tremor, anxiety, heat intolerance, fatigability, and dyspnea but do not suppress thyroid hormone synthesis. [24]",
        "For Graves disease, methimazole is the usual preferred thionamide outside pregnancy. A cited Graves regimen is methimazole 10-20 mg orally once daily until TSH normalizes; maintenance dosing is 5-15 mg/day. Antithyroid drugs inhibit thyroid peroxidase-dependent hormone synthesis. [19][21]",
        "Counsel every patient receiving methimazole or PTU about serious toxicity. Agranulocytosis occurs in approximately 0.2%-0.5% of patients receiving thionamides. PTU is associated with hepatotoxicity and vasculitis, while methimazole/carbimazole is associated with teratogenicity and pancreatitis. [18][19]",
        "Reserve PTU primarily for the first trimester of pregnancy or when methimazole cannot be tolerated; the FDA boxed warning describes severe and sometimes fatal liver injury with PTU. Switch to methimazole in the second and third trimesters. [18]"
      ],
      "bullets": [
        "Graves disease: a prolonged antithyroid-drug course, usually at least 12 months, may be used in an effort to induce remission. [19]",
        "Before radioiodine in severe hyperthyroidism or significant cardiac disease, selective methimazole pretreatment can reduce hormone stores and thyrotoxic complications; discontinue methimazole 3-5 days before I-131 when used. [16]",
        "Do not extrapolate thionamide treatment to thyroiditis or factitious thyrotoxicosis, because these are low-uptake states without active glandular overproduction. [7][8]"
      ],
      "subsections": [],
      "table": {
        "caption": "Thionamide selection and high-consequence safety considerations. [18][19][21]",
        "columns": [
          "Agent",
          "Preferred setting",
          "Key limitation"
        ],
        "rows": [
          [
            "Methimazole",
            "Usual first-line thionamide outside pregnancy; cited Graves dose 10-20 mg once daily. [19][21]",
            "Teratogenicity risk in the first trimester; severe adverse effects include agranulocytosis. [18][19]"
          ],
          [
            "Propylthiouracil",
            "First trimester of pregnancy, methimazole intolerance, or selected thyroid-storm treatment. [18][23]",
            "Severe hepatotoxicity, including acute liver failure; also associated with vasculitis and agranulocytosis. [18][19]"
          ]
        ]
      }
    },
    {
      "id": "definitive-treatment",
      "eyebrow": "Long-term control",
      "heading": "Choose radioiodine or thyroidectomy based on disease branch and treatment tradeoffs",
      "intro": "Definitive therapy applies to endogenous hyperthyroidism, not low-uptake destructive or exogenous states.",
      "paragraphs": [
        "Radioiodine therapy is an established definitive treatment for hyperthyroidism that reduces thyroid hormone synthesis through targeted beta radiation. It commonly results in permanent hypothyroidism; adverse effects include transient thyroiditis, sialadenitis, xerostomia, and rare secondary malignancy. [10][16]",
        "Anticipate a transient rise in circulating thyroid hormone after I-131 from damaged follicles releasing preformed T3 and T4. In severe hyperthyroidism or significant cardiac disease, use selective methimazole pretreatment, then stop methimazole 3-5 days before radioiodine to avoid reduced treatment efficacy. [16]",
        "Consider orbitopathy when selecting radioiodine for Graves disease. Graves ophthalmopathy may occur or worsen after radioiodine, particularly in smokers and in patients with severe hyperthyroidism. [10]",
        "Thyroidectomy is a definitive alternative when medical therapy is contraindicated or unsuccessful, including severe liver disease or leukopenia precluding thionamides, and can be used after stabilization as a bridge-to-definitive option in refractory severe disease. Patients with thyroid storm should generally be medically controlled before surgery. [17][22]"
      ],
      "bullets": [
        "For toxic multinodular goiter, radioiodine has been reported to reduce goiter size by about 40%. [10]",
        "After thyroid storm improves, discontinue iodine, taper and stop glucocorticoids, adjust beta-blockade, titrate thionamide therapy, and pursue radioiodine or thyroidectomy when indicated. [23]",
        "Shared selection among antithyroid drugs, radioiodine, and surgery should account for etiology, age, disease severity, goiter size, Graves orbitopathy, local resources, and patient preference. [24]"
      ],
      "subsections": [],
      "table": {
        "caption": "Definitive-therapy considerations for endogenous hyperthyroidism. [10][16][17][22][24]",
        "columns": [
          "Option",
          "Potential advantage",
          "Key tradeoff or precaution"
        ],
        "rows": [
          [
            "Radioiodine",
            "Definitive biochemical control without reoperation; can reduce toxic multinodular goiter size. [10][16]",
            "Permanent hypothyroidism is common; transient thyrotoxicosis may occur; Graves orbitopathy may worsen, particularly in smokers. [10][16]"
          ],
          [
            "Thyroidectomy",
            "Definitive option when thionamides cannot be used or severe disease requires a surgical pathway. [17]",
            "In thyroid storm, defer in most cases until medical control; consider only after failure of standard medical therapy in selected cases. [22]"
          ],
          [
            "Prolonged antithyroid drugs",
            "May induce Graves remission after a course usually lasting at least 12 months. [19]",
            "Requires toxicity surveillance; relapse after antithyroid drugs has been reported more often than after radioiodine or surgery. [24]"
          ]
        ]
      }
    }
  ],
  "faq": [],
  "references": [
    {
      "number": 1,
      "title": "Hyperthyroidism",
      "detail": "www.thelancet.com",
      "url": "https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(16)00278-6/fulltext",
      "authors": "www.thelancet.com",
      "host": "www.thelancet.com"
    },
    {
      "number": 2,
      "title": "Subclinical thyroid disease",
      "detail": "www.thelancet.com",
      "url": "https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(11)60276-6/fulltext?e-page-91fcdc6=2&e-page-92a6feb=5&e-page-76d2096=3&e-page-2e4fdd4=14&e-page-19fe3cd=108",
      "authors": "www.thelancet.com",
      "host": "www.thelancet.com"
    },
    {
      "number": 3,
      "title": "Hyperthyroidism in pregnancy",
      "detail": "www.thelancet.com",
      "url": "https://www.thelancet.com/journals/landia/article/PIIS2213-8587(13)70086-X/abstract",
      "authors": "www.thelancet.com",
      "host": "www.thelancet.com"
    },
    {
      "number": 4,
      "title": "Thyrotoxicosis",
      "detail": "www.thelancet.com",
      "url": "https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(11)60782-4/abstract",
      "authors": "www.thelancet.com",
      "host": "www.thelancet.com"
    },
    {
      "number": 5,
      "title": "Hyperthyroidism | Annals of Internal Medicine",
      "detail": "annals.org",
      "url": "https://annals.org/article.aspx?articleid=1206703",
      "authors": "annals.org",
      "host": "annals.org"
    },
    {
      "number": 6,
      "title": "Thyroid Function Test - an overview",
      "detail": "www.sciencedirect.com",
      "url": "https://www.sciencedirect.com/topics/biochemistry-genetics-and-molecular-biology/thyroid-function-test",
      "authors": "www.sciencedirect.com",
      "host": "www.sciencedirect.com"
    },
    {
      "number": 7,
      "title": "Euthyroidism - an overview | ScienceDirect Topics",
      "detail": "www.sciencedirect.com",
      "url": "https://www.sciencedirect.com/topics/biochemistry-genetics-and-molecular-biology/euthyroidism",
      "authors": "www.sciencedirect.com",
      "host": "www.sciencedirect.com"
    },
    {
      "number": 8,
      "title": "Thyroid Stimulating Immunoglobulin - an overview",
      "detail": "www.sciencedirect.com",
      "url": "https://www.sciencedirect.com/topics/neuroscience/thyroid-stimulating-immunoglobulin",
      "authors": "www.sciencedirect.com",
      "host": "www.sciencedirect.com"
    },
    {
      "number": 9,
      "title": "Thyroid Peroxidase Antibody - an overview",
      "detail": "www.sciencedirect.com",
      "url": "https://www.sciencedirect.com/topics/pharmacology-toxicology-and-pharmaceutical-science/thyroid-peroxidase-antibody",
      "authors": "www.sciencedirect.com",
      "host": "www.sciencedirect.com"
    },
    {
      "number": 10,
      "title": "Diagnosis and Management of Thyrotoxicosis",
      "detail": "applications.emro.who.int",
      "url": "https://applications.emro.who.int/imemrf/Egypt_J_Hosp_Med/Egypt_J_Hosp_Med_2017_69_6_2743_2749.pdf",
      "authors": "applications.emro.who.int",
      "host": "applications.emro.who.int"
    },
    {
      "number": 11,
      "title": "Guideline for the prevention, diagnosis and treatment of infertility",
      "detail": "iris.who.int",
      "url": "https://iris.who.int/server/api/core/bitstreams/0b4b00be-9412-4d73-a3a9-1fb00874fdb6/content",
      "authors": "iris.who.int",
      "host": "iris.who.int"
    },
    {
      "number": 12,
      "title": "Thyroid Function Tests",
      "detail": "www.thyroid.org",
      "url": "https://www.thyroid.org/thyroid-function-tests",
      "authors": "www.thyroid.org",
      "host": "www.thyroid.org"
    },
    {
      "number": 13,
      "title": "Thyroid Health Blog: Hyperthyroidism Awareness |  American Thyroid Association",
      "detail": "www.thyroid.org",
      "url": "https://www.thyroid.org/hyperthyroidism-awareness-diagnosis-options",
      "authors": "www.thyroid.org",
      "host": "www.thyroid.org"
    },
    {
      "number": 14,
      "title": "Pediatric Thyroid Function Tests |  American Thyroid Association",
      "detail": "www.thyroid.org",
      "url": "https://www.thyroid.org/pediatric-thyroid-function",
      "authors": "www.thyroid.org",
      "host": "www.thyroid.org"
    },
    {
      "number": 15,
      "title": "ATA Guidelines & Statements |  American Thyroid Association",
      "detail": "www.thyroid.org",
      "url": "https://www.thyroid.org/professionals/ata-professional-guidelines",
      "authors": "www.thyroid.org",
      "host": "www.thyroid.org"
    },
    {
      "number": 16,
      "title": "Radioactive Iodine (I-131) Therapy for Hyperthyroidism and Thyroid Cancer - StatPearls - NCBI Bookshelf",
      "detail": "www.ncbi.nlm.nih.gov",
      "url": "https://www.ncbi.nlm.nih.gov/books/NBK557741",
      "authors": "www.ncbi.nlm.nih.gov",
      "host": "www.ncbi.nlm.nih.gov"
    },
    {
      "number": 17,
      "title": "Clinical Review and Update on the Management of Thyroid Storm",
      "detail": "pmc.ncbi.nlm.nih.gov",
      "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC9462913",
      "authors": "pmc.ncbi.nlm.nih.gov",
      "host": "pmc.ncbi.nlm.nih.gov"
    },
    {
      "number": 18,
      "title": "Acute and emergency care for thyrotoxicosis and thyroid storm - PMC",
      "detail": "pmc.ncbi.nlm.nih.gov",
      "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC5667251",
      "authors": "pmc.ncbi.nlm.nih.gov",
      "host": "pmc.ncbi.nlm.nih.gov"
    },
    {
      "number": 19,
      "title": "Management of thyrotoxicosis: anti thyroid drugs - NCBI Bookshelf",
      "detail": "www.ncbi.nlm.nih.gov",
      "url": "https://www.ncbi.nlm.nih.gov/books/NBK577216",
      "authors": "www.ncbi.nlm.nih.gov",
      "host": "www.ncbi.nlm.nih.gov"
    },
    {
      "number": 20,
      "title": "The efficiency and safety of methimazole and propylthiouracil in hyperthyroidism",
      "detail": "pmc.ncbi.nlm.nih.gov",
      "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC8322508",
      "authors": "pmc.ncbi.nlm.nih.gov",
      "host": "pmc.ncbi.nlm.nih.gov"
    },
    {
      "number": 21,
      "title": "Methimazole - StatPearls - NCBI Bookshelf",
      "detail": "www.ncbi.nlm.nih.gov",
      "url": "https://www.ncbi.nlm.nih.gov/books/NBK545223",
      "authors": "www.ncbi.nlm.nih.gov",
      "host": "www.ncbi.nlm.nih.gov"
    },
    {
      "number": 22,
      "title": "Approach to the patient with thyroid storm",
      "detail": "pmc.ncbi.nlm.nih.gov",
      "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC13099200",
      "authors": "pmc.ncbi.nlm.nih.gov",
      "host": "pmc.ncbi.nlm.nih.gov"
    },
    {
      "number": 23,
      "title": "Thyroid Storm - StatPearls - NCBI Bookshelf - NIH",
      "detail": "www.ncbi.nlm.nih.gov",
      "url": "https://www.ncbi.nlm.nih.gov/books/NBK448095",
      "authors": "www.ncbi.nlm.nih.gov",
      "host": "www.ncbi.nlm.nih.gov"
    },
    {
      "number": 24,
      "title": "A multi-center, open label, randomised, parallel-group study to",
      "detail": "cdn.clinicaltrials.gov",
      "url": "https://cdn.clinicaltrials.gov/large-docs/53/NCT03303053/Prot_SAP_000.pdf",
      "authors": "cdn.clinicaltrials.gov",
      "host": "cdn.clinicaltrials.gov"
    }
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  "citations": [
    {
      "number": 1,
      "title": "Hyperthyroidism",
      "detail": "www.thelancet.com",
      "url": "https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(16)00278-6/fulltext",
      "authors": "www.thelancet.com",
      "host": "www.thelancet.com",
      "snippet": "The most common cause of hyperthyroidism is Graves' disease, followed by toxic nodular goitre. Other important causes of thyrotoxicosis include thyroiditis,",
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    {
      "number": 2,
      "title": "Subclinical thyroid disease",
      "detail": "www.thelancet.com",
      "url": "https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(11)60276-6/fulltext?e-page-91fcdc6=2&e-page-92a6feb=5&e-page-76d2096=3&e-page-2e4fdd4=14&e-page-19fe3cd=108",
      "authors": "www.thelancet.com",
      "host": "www.thelancet.com",
      "snippet": "hyperthyroidism was subclinical in most patients with toxic multinodular goitre (57%) but in fewer than 10% of those with Graves' disease.24",
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    {
      "number": 3,
      "title": "Hyperthyroidism in pregnancy",
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      "url": "https://www.thelancet.com/journals/landia/article/PIIS2213-8587(13)70086-X/abstract",
      "authors": "www.thelancet.com",
      "host": "www.thelancet.com",
      "snippet": "by DS Cooper · 2013 · Cited by 438 — Graves' disease, which is autoimmune in nature, is the usual cause; but hyperthyroidism in pregnancy can be caused by any type of hyperthyroidism—eg, toxic",
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      "authors": "www.thelancet.com",
      "host": "www.thelancet.com",
      "snippet": "by JA Franklyn · 2012 · Cited by 407 — Antithyroid drugs are the usual initial treatment (thionamides such as carbimazole or its active metabolite methimazole are the drugs of choice)",
      "score": 0.21820295
    },
    {
      "number": 5,
      "title": "Hyperthyroidism | Annals of Internal Medicine",
      "detail": "annals.org",
      "url": "https://annals.org/article.aspx?articleid=1206703",
      "authors": "annals.org",
      "host": "annals.org",
      "snippet": "Hyperthyroidism associated with high RAIU usually results from 1 of 3 disorders: Graves disease, toxic multinodular goiter, or a toxic adenoma.",
      "score": 0.5715041
    },
    {
      "number": 6,
      "title": "Thyroid Function Test - an overview",
      "detail": "www.sciencedirect.com",
      "url": "https://www.sciencedirect.com/topics/biochemistry-genetics-and-molecular-biology/thyroid-function-test",
      "authors": "www.sciencedirect.com",
      "host": "www.sciencedirect.com",
      "snippet": "### 9.5 Thyroid Function Tests\n\nThe most commonly ordered thyroid function test is TSH followed by T4 (total or free), and T3 (total or free). More recently, FT4 and FT3 tests have been ordered more frequently than T4 and T3 tests. TSH is used as a screening test for thyroid status. It is elevated i",
      "score": 0.6208291
    },
    {
      "number": 7,
      "title": "Euthyroidism - an overview | ScienceDirect Topics",
      "detail": "www.sciencedirect.com",
      "url": "https://www.sciencedirect.com/topics/biochemistry-genetics-and-molecular-biology/euthyroidism",
      "authors": "www.sciencedirect.com",
      "host": "www.sciencedirect.com",
      "snippet": "In general, freeT3/total T3 measures do not usually add much to the diagnosis of hyperthyroidism outside of this setting and routine measurement is discouraged.\n\n##### 2.3.5.4 Nuclear imaging is often required to definitively diagnose the cause of hyperthyroidism\n\nBeyond the scope of this text, eith",
      "score": 0.5383771
    },
    {
      "number": 8,
      "title": "Thyroid Stimulating Immunoglobulin - an overview",
      "detail": "www.sciencedirect.com",
      "url": "https://www.sciencedirect.com/topics/neuroscience/thyroid-stimulating-immunoglobulin",
      "authors": "www.sciencedirect.com",
      "host": "www.sciencedirect.com",
      "snippet": "of _subclinical_ hyperthyroidism. A TSH level less than 0.03 mU/L with elevated T 3 and T 4 is diagnostic of _overt_ hyperthyroidism. Overt hypothyroidism is diagnosed if TSH levels are more than 20 mU/L (even as high as 200-400 mU/L) with reduced levels of T 3 and T 4. Subclinical hypothyroidism is",
      "score": 0.52100873
    },
    {
      "number": 9,
      "title": "Thyroid Peroxidase Antibody - an overview",
      "detail": "www.sciencedirect.com",
      "url": "https://www.sciencedirect.com/topics/pharmacology-toxicology-and-pharmaceutical-science/thyroid-peroxidase-antibody",
      "authors": "www.sciencedirect.com",
      "host": "www.sciencedirect.com",
      "snippet": "The diagnosis of thyrotoxicosis is clear with an elevated free T4 and low TSH. However, a low TSH with a low or normal free T4 has several additional diagnoses to consider other than subclinical hyperthyroidism (see Fig. 24.9). Diagnosis of thyrotoxicosis during pregnancy should be made more cautiou",
      "score": 0.507544
    },
    {
      "number": 10,
      "title": "Diagnosis and Management of Thyrotoxicosis",
      "detail": "applications.emro.who.int",
      "url": "https://applications.emro.who.int/imemrf/Egypt_J_Hosp_Med/Egypt_J_Hosp_Med_2017_69_6_2743_2749.pdf",
      "authors": "applications.emro.who.int",
      "host": "applications.emro.who.int",
      "snippet": "care physicians must keep a high degree of suspicion in order to provide prompt therapeutic measures to avoid complications as well as death of patient. Keywords: thyrotoxicosis, diagnosis of thyrotoxicosis, thyroid storm, management of thyroid storm, anti-thyroid drugs, thyroidectomy INTRODUCTION H",
      "score": 0.5900477
    },
    {
      "number": 11,
      "title": "Guideline for the prevention, diagnosis and treatment of infertility",
      "detail": "iris.who.int",
      "url": "https://iris.who.int/server/api/core/bitstreams/0b4b00be-9412-4d73-a3a9-1fb00874fdb6/content",
      "authors": "iris.who.int",
      "host": "iris.who.int",
      "snippet": "TSH When thyroid antibodies are present, both hypothyroidism and hyperthyroidism are more frequent in women with infertility (32). Both hyperthyroidism and hypothyroidism can lead to menstrual disturbances (32, 33) and may result in changes in sex hormone binding globulin (SHBG) and sex steroids (32",
      "score": 0.5035894
    },
    {
      "number": 12,
      "title": "Thyroid Function Tests",
      "detail": "www.thyroid.org",
      "url": "https://www.thyroid.org/thyroid-function-tests",
      "authors": "www.thyroid.org",
      "host": "www.thyroid.org",
      "snippet": "T3 TESTS  \nT3 tests are often useful to diagnosis hyperthyroidism or to determine the severity of the hyperthyroidism. Patients who are hyperthyroid will have an elevated T3 level. In some individuals with a low TSH, only the T3 is elevated and the FT4 or FTI is normal. T3 testing rarely is helpful ",
      "score": 0.50183165
    },
    {
      "number": 13,
      "title": "Thyroid Health Blog: Hyperthyroidism Awareness |  American Thyroid Association",
      "detail": "www.thyroid.org",
      "url": "https://www.thyroid.org/hyperthyroidism-awareness-diagnosis-options",
      "authors": "www.thyroid.org",
      "host": "www.thyroid.org",
      "snippet": "Once a suppressed thyrotropin (TSH) has been detected, further investigation with serum triiodothyronine (T3) and free thyroxine (free T4) can help delineate overt from subclinical disease. A thorough history of past thyroid disease, as well as current medications and supplements, can help detect an",
      "score": 0.45304462
    },
    {
      "number": 14,
      "title": "Pediatric Thyroid Function Tests |  American Thyroid Association",
      "detail": "www.thyroid.org",
      "url": "https://www.thyroid.org/pediatric-thyroid-function",
      "authors": "www.thyroid.org",
      "host": "www.thyroid.org",
      "snippet": "T4 TESTS\n\nTests for T4 measure all of the T4 (bound and free). Free T4 (FT4) measures the amount of thyroid hormone (T4) circulating in the blood and free to enter cells to do its work. Other similar measures exist, such as the free T4 index (FTI).\n\nFigure 1\n\nFigure 1\n\n### MEDICATIONS/SUPPLEMENTS TH",
      "score": 0.41748574
    },
    {
      "number": 15,
      "title": "ATA Guidelines & Statements |  American Thyroid Association",
      "detail": "www.thyroid.org",
      "url": "https://www.thyroid.org/professionals/ata-professional-guidelines",
      "authors": "www.thyroid.org",
      "host": "www.thyroid.org",
      "snippet": "Additional Resources\n\nthy.2016.26.issue-10  \n2016 American Thyroid Association Guidelines for Diagnosis and Management of Hyperthyroidism and other causes of Thyrotoxicosis  \nRoss, Burch, et al.,Thyroid. Oct 2016, 26(10): 1343-1421.\n\nthy.2016.26.issue-10\n\nAdditional Resources\n\nthy.2016.26.issue-1  \n",
      "score": 0.2862146
    },
    {
      "number": 16,
      "title": "Radioactive Iodine (I-131) Therapy for Hyperthyroidism and Thyroid Cancer - StatPearls - NCBI Bookshelf",
      "detail": "www.ncbi.nlm.nih.gov",
      "url": "https://www.ncbi.nlm.nih.gov/books/NBK557741",
      "authors": "www.ncbi.nlm.nih.gov",
      "host": "www.ncbi.nlm.nih.gov",
      "snippet": "Although generally contraindicated due to reduced efficacy, methimazole may be used selectively before RAI therapy in patients with severe hyperthyroidism or significant cardiac disease. Transient thyrotoxicosis may occur following I-131 administration due to release of preformed triiodothyronine an",
      "score": 0.8201387
    },
    {
      "number": 17,
      "title": "Clinical Review and Update on the Management of Thyroid Storm",
      "detail": "pmc.ncbi.nlm.nih.gov",
      "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC9462913",
      "authors": "pmc.ncbi.nlm.nih.gov",
      "host": "pmc.ncbi.nlm.nih.gov",
      "snippet": "Patients with severe symptoms and rapid deterioration;\n\n   Contraindications to medical therapy - Liver disease or leukopenia precluding use of PTU/methimazole, hyperthyroidism caused by molar pregnancy, Graves’ disease-related ophthalmopathy;\n\n   Amiodarone induced thyrotoxicosis due to the long ha",
      "score": 0.7593865
    },
    {
      "number": 18,
      "title": "Acute and emergency care for thyrotoxicosis and thyroid storm - PMC",
      "detail": "pmc.ncbi.nlm.nih.gov",
      "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC5667251",
      "authors": "pmc.ncbi.nlm.nih.gov",
      "host": "pmc.ncbi.nlm.nih.gov",
      "snippet": "As for PTU, the dose for thyroid storm is 600–1,000 mg given orally as a loading dose followed by 200–250 mg every 4 h. The total daily dose is between 1,200 and 1,500 mg. The drug can be given through a nasogastric tube or rectally. Outside the thyroid gland, only PTU, not methimazole, can inhibit ",
      "score": 0.7443038
    },
    {
      "number": 19,
      "title": "Management of thyrotoxicosis: anti thyroid drugs - NCBI Bookshelf",
      "detail": "www.ncbi.nlm.nih.gov",
      "url": "https://www.ncbi.nlm.nih.gov/books/NBK577216",
      "authors": "www.ncbi.nlm.nih.gov",
      "host": "www.ncbi.nlm.nih.gov",
      "snippet": "Both carbimazole and propylthiouracil may have minor side effects in up to 5% of people using these medications. These adverse effects include cutaneous allergic reactions, arthralgias and gastro-intestinal upset. Severe side-effects are rare but include agranulocytosis in 0.2–0.5% of patients and m",
      "score": 0.7395922
    },
    {
      "number": 20,
      "title": "The efficiency and safety of methimazole and propylthiouracil in hyperthyroidism",
      "detail": "pmc.ncbi.nlm.nih.gov",
      "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC8322508",
      "authors": "pmc.ncbi.nlm.nih.gov",
      "host": "pmc.ncbi.nlm.nih.gov",
      "snippet": "Although MMI and PTU were validated to have effects on treating hyperthyroidism, they might have adverse reactions. Previously, a study has demonstrated that PTU has a high risk of adverse reactions compared with MMI in the treatment of hyperthyroidism. Meanwhile, another study has suggested that PT",
      "score": 0.7355091
    },
    {
      "number": 21,
      "title": "Methimazole - StatPearls - NCBI Bookshelf",
      "detail": "www.ncbi.nlm.nih.gov",
      "url": "https://www.ncbi.nlm.nih.gov/books/NBK545223",
      "authors": "www.ncbi.nlm.nih.gov",
      "host": "www.ncbi.nlm.nih.gov",
      "snippet": "Older patients: Methimazole is prescribed to treat hyperthyroidism in older patients unsuitable for surgery or radioactive iodine therapy. The severity of hyperthyroidism determines the initial dosage of methimazole for older patients and typically ranges from 15 to 60 mg/d. This dosage is divided i",
      "score": 0.7077487
    },
    {
      "number": 22,
      "title": "Approach to the patient with thyroid storm",
      "detail": "pmc.ncbi.nlm.nih.gov",
      "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC13099200",
      "authors": "pmc.ncbi.nlm.nih.gov",
      "host": "pmc.ncbi.nlm.nih.gov",
      "snippet": "Management requires immediate supportive therapy, including cardiovascular stabilization, respiratory support, and temperature control, along with identification and treatment of precipitating factors. Pharmacologic therapy involves antithyroid agents to block thyroid hormone synthesis, beta blocker",
      "score": 0.7016523
    },
    {
      "number": 23,
      "title": "Thyroid Storm - StatPearls - NCBI Bookshelf - NIH",
      "detail": "www.ncbi.nlm.nih.gov",
      "url": "https://www.ncbi.nlm.nih.gov/books/NBK448095",
      "authors": "www.ncbi.nlm.nih.gov",
      "host": "www.ncbi.nlm.nih.gov",
      "snippet": "After initial supportive measures, a beta-blocker should be started for any case of a suspected thyroid storm. Typically, propranolol 40 mg to 80 mg is given every 4 to 6 hours. Then, a loading dose of propylthiouracil (PTU) 500 mg to 1000 mg followed by 250 mg every 4 hours or Methimazole (MMI) 20 ",
      "score": 0.68140936
    },
    {
      "number": 24,
      "title": "A multi-center, open label, randomised, parallel-group study to",
      "detail": "cdn.clinicaltrials.gov",
      "url": "https://cdn.clinicaltrials.gov/large-docs/53/NCT03303053/Prot_SAP_000.pdf",
      "authors": "cdn.clinicaltrials.gov",
      "host": "cdn.clinicaltrials.gov",
      "snippet": "and severity of Graves’ opthalmopathy, local practices and resources. ATDs including methimazole, carbimazole, and propylthiouracil are effective treatments that inhibit thyroid hormone synthesis, and have clinically important immunosuppresive effects including reducing serum antithyrotropin recepto",
      "score": 0.64020914
    }
  ],
  "publishedAt": "2026-08-21T02:10:10.485059+00:00",
  "updatedAt": "2026-08-21T02:10:10.485059+00:00",
  "readingMinutes": 6,
  "slug": "hyperthyroidism"
}