What is the treatment for hyperthyroidism?

Treatment of Hyperthyroidism

The first-line treatment for hyperthyroidism is thionamide therapy with methimazole (preferred) or propylthiouracil, along with beta-blockers for symptomatic relief, while definitive treatment options include radioactive iodine ablation (most widely used in the US) or surgical thyroidectomy based on the underlying cause and patient factors. 1, 2

Diagnosis Confirmation

Before initiating treatment, confirm hyperthyroidism with:

• Suppressed TSH
• Elevated Free T4 and/or Free T3
• Determine etiology through:
  • Clinical presentation
  • TSH receptor antibodies
  • Thyroid ultrasonography
  • Thyroid scintigraphy (if nodules present or etiology unclear)

Treatment Options

1. Antithyroid Medications

• Methimazole (First-line) 1, 3

  • Initial dose: 10-30 mg daily (based on severity)
  • Mechanism: Inhibits thyroid hormone synthesis
  • Standard course: 12-18 months
  • Monitoring: Thyroid function every 2-3 weeks initially
  • Potential adverse effects: Agranulocytosis, skin eruptions, hepatotoxicity

• Propylthiouracil (Alternative) 4

  • Dosing: 100-300 mg divided three times daily
  • Used when methimazole is contraindicated or in first trimester of pregnancy
  • Additional benefit: Inhibits peripheral conversion of T4 to T3
  • Serious risks: Severe liver problems including liver failure

2. Symptomatic Treatment

• Beta-blockers 1
  • Indicated for all symptomatic patients
  • Options: Atenolol 25-50 mg daily or propranolol
  • Addresses: Palpitations, tremor, anxiety, tachycardia
  • Caution: May cause bradycardia, bronchospasm, hypotension

3. Definitive Treatment Options

• Radioactive Iodine Ablation 2, 5

  • Most widely used treatment in the United States
  • Particularly effective for toxic nodular goiter
  • Contraindicated in pregnancy
  • Results in permanent hypothyroidism requiring lifelong thyroid replacement

• Surgical Thyroidectomy 1, 5

  • Indicated for:
    • Large goiters causing compressive symptoms
    • Suspicious nodules
    • Patients who decline radioactive iodine
    • Pregnant women who cannot tolerate antithyroid drugs
  • Risks: Hypoparathyroidism, recurrent laryngeal nerve injury

Treatment Algorithm Based on Etiology

Graves' Disease

1. Initial treatment with antithyroid drugs (methimazole preferred)
2. Consider definitive treatment if relapse occurs (50% recurrence rate after 12-18 months of antithyroid drugs) 5
3. Long-term antithyroid therapy (5-10 years) may be considered with lower recurrence rates (15%) 5

Toxic Nodular Goiter

1. Typically treated with radioactive iodine or thyroidectomy 5
2. Antithyroid drugs less effective long-term due to high relapse rates 6

Thyroiditis (Destructive Thyrotoxicosis)

1. Usually self-limiting and transient
2. Symptomatic treatment with beta-blockers
3. Steroids only in severe cases 5

Special Populations

Pregnancy

• First trimester: Propylthiouracil preferred 1, 4
• Second and third trimesters: Switch to methimazole 1
• Use lowest effective dose
• Radioactive iodine absolutely contraindicated 1

Elderly Patients

• Treatment recommended even for subclinical hyperthyroidism (TSH <0.1 mIU/L) due to higher risk of cardiovascular complications 7, 1

Thyroid Storm (Emergency)

• Life-threatening condition requiring immediate intensive care 1, 8
• Treatment includes:
  • High-dose antithyroid drugs
  • Beta-blockers
  • Corticosteroids
  • Supportive care

Monitoring and Follow-up

• Initial monitoring: Every 2-3 weeks until stable 1
• Once stable: Every 1-3 months
• Adjust medication dose based on thyroid function tests
• Monitor for medication side effects

Common Pitfalls

• Failing to recognize thyroid storm
• Missing the underlying cause of hyperthyroidism
• Inadequate monitoring for medication side effects
• Ignoring cardiovascular complications
• Overlooking pregnancy status when selecting treatment

By following this treatment approach, hyperthyroidism can be effectively managed to reduce morbidity and mortality associated with untreated disease 5, 9.