What are the treatment options for hyperthyroidism?

Treatment Options for Hyperthyroidism

The primary treatment options for hyperthyroidism include antithyroid medications (thionamides), radioactive iodine ablation, and surgical thyroidectomy, with the choice depending on the underlying cause, patient factors, and disease severity. 1, 2

Initial Evaluation and Diagnosis

Before initiating treatment, proper diagnosis is essential:

• Confirm hyperthyroidism with laboratory tests:

  • Suppressed TSH
  • Elevated Free T4 and/or Free T3
  • Determine etiology through clinical presentation, TSH receptor antibodies, thyroid ultrasonography, and thyroid scintigraphy 1

• Common causes of hyperthyroidism:

  • Graves' disease (70% of cases)
  • Toxic multinodular goiter (16%)
  • Thyroiditis (3%)
  • Drug-induced hyperthyroidism (9%) 3

First-Line Symptomatic Treatment

• Beta-blockers (such as atenolol 25-50 mg daily or propranolol) should be initiated for all symptomatic patients to address:
  • Palpitations
  • Tremor
  • Anxiety
  • Other adrenergic symptoms 1

Definitive Treatment Options

1. Antithyroid Medications

• Thionamides: Methimazole (preferred) or Propylthiouracil
  • Mechanism: Inhibit thyroid hormone synthesis
  • Dosing:
    • Initial: Methimazole 10-30 mg daily based on severity
    • Propylthiouracil 100-300 mg divided three times daily 4, 5
  • Duration:
    • Standard course: 12-18 months
    • Long-term treatment (5-10 years) associated with fewer recurrences (15% vs 50%) 3
  • Monitoring:
    • Thyroid function tests every 2-3 weeks initially
    • Once clinical improvement occurs, adjust to maintenance dose 1
  • Side effects:
    • Minor: Rash, urticaria, arthralgia
    • Serious: Agranulocytosis, hepatotoxicity, vasculitis 5

2. Radioactive Iodine (RAI) Therapy

• Most widely used treatment in the United States 2
• Permanently damages thyroid cells that take up iodine
• Advantages:
  • Definitive treatment with high success rate
  • Avoids surgery risks
• Disadvantages:
  • Often results in hypothyroidism requiring lifelong thyroid hormone replacement
  • Contraindicated in pregnancy
  • May worsen Graves' ophthalmopathy 3

3. Surgical Thyroidectomy

• Indications:
  • Large goiters causing compressive symptoms
  • Suspicious nodules
  • Pregnant women who cannot tolerate antithyroid drugs
  • Patient preference
• Advantages:
  • Rapid resolution of hyperthyroidism
  • Definitive treatment
• Disadvantages:
  • Surgical risks including hypoparathyroidism and recurrent laryngeal nerve injury
  • Requires lifelong thyroid hormone replacement 1, 2

Treatment Selection Based on Cause

Graves' Disease

• First-line: Antithyroid drugs (methimazole preferred)
• Alternative options:
  • RAI therapy (most common in US)
  • Thyroidectomy
• Recurrence after antithyroid drugs occurs in approximately 50% of patients 3
• Risk factors for recurrence:
  • Age <40 years
  • High FT4 levels (≥40 pmol/L)
  • High TSH-binding inhibitory immunoglobulins
  • Large goiter 3

Toxic Nodular Goiter

• Preferred treatments:
  • RAI therapy
  • Thyroidectomy
• Less commonly: Radiofrequency ablation 3

Thyroiditis

• Usually self-limiting
• Supportive care with beta-blockers for symptoms
• Steroids only in severe cases 3

Special Populations

Pregnant Women

• Propylthiouracil is preferred in the first trimester
• Methimazole is preferred in the second and third trimesters
• Use lowest effective dose to minimize fetal risks 1
• RAI is absolutely contraindicated 4

Elderly Patients

• Treatment recommended even for subclinical hyperthyroidism (TSH <0.1 mIU/L) due to increased risk of:
  • Atrial fibrillation
  • Heart failure
  • Osteoporosis
  • Fractures 1, 6

Common Pitfalls to Avoid

• Failing to recognize thyroid storm (life-threatening emergency)
• Missing the underlying cause of hyperthyroidism
• Inadequate monitoring of thyroid function during treatment
• Overlooking pregnancy status before initiating treatment
• Ignoring cardiovascular complications 1

Treatment Algorithm

1. Confirm diagnosis with TSH, Free T4/T3
2. Start beta-blocker for symptomatic relief
3. Choose definitive treatment based on:
   • Underlying cause
   • Patient age and comorbidities
   • Pregnancy status
   • Patient preference
4. Monitor response and adjust treatment accordingly
5. Treat until remission or consider definitive therapy if relapse occurs

The treatment approach should be tailored based on the specific cause of hyperthyroidism, with careful consideration of patient factors and potential complications 1, 3, 6.