What are the initial treatment recommendations for hyperthyroidism?

Hyperthyroidism Treatment and Management

Initial Diagnostic Workup

Confirm hyperthyroidism biochemically with TSH and free T4 (FT4) testing; if symptomatic with minimal FT4 elevation, add T3 measurement. 1

• Check TSH receptor antibodies if clinical features suggest Graves' disease (ophthalmopathy, diffuse goiter, or T3 toxicosis) 1
• Perform thyroid ultrasonography and scintigraphy if thyroid nodules are present or etiology is unclear 2
• Physical examination findings of ophthalmopathy or thyroid bruit are diagnostic of Graves' disease and warrant early endocrine referral 1

Treatment Algorithm by Severity

Mild Symptoms (Grade 1)

Start beta-blocker therapy (atenolol 25-50 mg daily or propranolol) for symptomatic relief while determining definitive treatment. 1

• Continue monitoring thyroid function every 2-3 weeks to detect transition to hypothyroidism, which commonly occurs with transient thyroiditis 1
• If thyrotoxicosis persists beyond 6 weeks, obtain endocrine consultation for additional workup 1

Moderate Symptoms (Grade 2)

Initiate beta-blocker therapy and provide hydration with supportive care; consider endocrine consultation. 1

• For persistent thyrotoxicosis beyond 6 weeks, refer to endocrinology for possible medical thyroid suppression 1
• Monitor closely with symptom evaluation and free T4 testing every 2 weeks 1

Severe Symptoms (Grade 3-4)

Hospitalize immediately and obtain urgent endocrine consultation for all patients. 1

• Administer beta-blocker (atenolol or propranolol) with hydration and supportive care 1
• Inpatient endocrine consultation guides use of additional therapies including steroids, SSKI, or thionamides (methimazole or propylthiouracil), and possible surgery 1

Definitive Treatment Options

Antithyroid Drug Therapy

Methimazole is the preferred antithyroid drug for most patients, except during the first trimester of pregnancy when propylthiouracil should be used. 1, 3

• Propylthiouracil carries a black box warning for severe liver injury and hepatic failure, including cases requiring liver transplantation or resulting in death, and should be reserved for patients who cannot tolerate methimazole or during/just prior to the first trimester of pregnancy. 3
• Standard treatment duration is 12-18 months using titration method (lowest dose maintaining euthyroidism) 4
• Long-term treatment (5-10 years) is associated with fewer recurrences (15%) compared to short-term treatment (50% recurrence rate) 5
• Patients should report immediately any symptoms of hepatic dysfunction (anorexia, pruritus, jaundice, right upper quadrant pain, dark urine) or illness (sore throat, fever, rash) suggesting agranulocytosis 3

Risk Factors for Recurrence After Antithyroid Drugs

Recurrence risk increases with: age younger than 40 years, FT4 ≥40 pmol/L, TSH-binding inhibitory immunoglobulins >6 U/L, and goiter size ≥WHO grade 2 before treatment 5

Radioactive Iodine Ablation

Radioactive iodine is the most widely used treatment in the United States and is preferred for toxic nodular goiter. 6, 5

• Contraindicated in pregnancy 1
• Preferred for patients with contraindications to antithyroid drugs or after failed medical therapy 6

Surgical Thyroidectomy

Surgery is indicated for patients with large goiters causing compressive symptoms, contraindications to other therapies, or patient preference. 6, 5

• Reserved for patients who do not respond to thioamide therapy 1
• Appropriate for toxic nodular goiter when radioiodine is not suitable 5

Special Populations

Pregnancy

Propylthiouracil may be the treatment of choice during or just prior to the first trimester of pregnancy; consider switching to methimazole for second and third trimesters given maternal hepatotoxicity risk. 1, 3

• Use lowest possible thioamide dose to maintain FT4 in high-normal range 1
• Monitor FT4 or free thyroxine index every 2-4 weeks 1
• Beta-blockers (propranolol) can reduce symptoms until thioamide therapy takes effect 1

Thyroiditis-Induced Thyrotoxicosis

Thyroiditis is self-limited and typically resolves within weeks with supportive care, most often transitioning to primary hypothyroidism. 1

• Treat with beta-blockers for symptomatic relief only 1
• High-dose corticosteroids are not routinely required 1
• Monitor for transition to hypothyroidism and initiate thyroid hormone replacement when TSH becomes elevated with low FT4 1

Graves' Disease

Graves' disease is persistent and requires definitive treatment with antithyroid drugs, radioactive iodine, or surgery. 1

• Endocrine consultation is recommended for all suspected cases 1
• Standard therapy for hyperthyroidism should be followed per established guidelines 1

Critical Monitoring Parameters

• Monitor thyroid function tests every 4-6 weeks during routine follow-up 1
• Check prothrombin time before surgical procedures due to potential hypoprothrombinemia 3
• Obtain white blood cell and differential counts if symptoms of infection develop (fever, sore throat) to assess for agranulocytosis 3
• Monitor for vasculitis symptoms: new rash, hematuria, decreased urine output, dyspnea, or hemoptysis 3