What are the treatment options for hyperthyroidism?

Treatment Options for Hyperthyroidism

The preferred first-line treatment for hyperthyroidism is methimazole, with radioactive iodine ablation and surgical thyroidectomy as definitive treatment options for appropriate candidates. 1

Medication Therapy

First-Line Antithyroid Drugs

• Methimazole (MMI):

  • Preferred first-line medication for most patients 1
  • Initial dosing: 10-30 mg once daily
  • Standard treatment course: 12-18 months
  • More effective than PTU in inducing euthyroidism 2
  • Contraindicated in first trimester of pregnancy

• Propylthiouracil (PTU):

  • Alternative when methimazole is not tolerated
  • Dosing: 100-300 mg divided three times daily
  • First-line during first trimester of pregnancy 1, 3
  • Associated with higher risk of severe liver injury, especially in pediatric patients 3
  • Less convenient dosing schedule (three times daily vs. once daily for MMI)

Adjunctive Therapy

• Beta-blockers (atenolol, propranolol):
  • Indicated for all symptomatic patients 1
  • Address palpitations, tremor, anxiety, and tachycardia
  • Caution in patients with asthma, bradycardia, or heart failure
  • May require dose adjustment when patient becomes euthyroid 3

Definitive Treatment Options

Radioactive Iodine (RAI) Ablation

• Most widely used definitive treatment in the United States 4
• Particularly effective for toxic nodular goiter 1, 5
• Advantages:
  • Outpatient procedure
  • High success rate
  • No surgical risks
• Contraindications:
  • Absolutely contraindicated in pregnancy 1, 3
  • Not recommended in active severe ophthalmopathy
  • Contraindicated in patients planning pregnancy within 4-6 months

Surgical Thyroidectomy

• Indications 1:
  • Large goiters causing compressive symptoms
  • Suspicious thyroid nodules
  • Patients who decline RAI
  • Pregnant women who cannot tolerate antithyroid drugs
• Risks:
  • Hypoparathyroidism
  • Recurrent laryngeal nerve injury
  • General surgical risks

Special Populations

Pregnancy

• First trimester: Propylthiouracil is preferred 1, 3
• Second and third trimesters: Switch to methimazole 1, 3
• Use lowest effective dose to minimize fetal effects
• RAI is absolutely contraindicated 1
• Surgery considered if medication intolerance occurs

Subclinical Hyperthyroidism

• Treatment recommended for:
  • TSH <0.1 mIU/L
  • Patients over 65 years
  • Those with cardiovascular disease or osteoporosis risk 1, 6

Monitoring and Follow-up

• Initial monitoring every 2-3 weeks until stable, then every 1-3 months 1
• Monitor for medication side effects:
  • Agranulocytosis (sore throat, fever)
  • Skin eruptions
  • Hepatotoxicity (jaundice, right upper quadrant pain) 3
  • Vasculitis (rash, hematuria, dyspnea) 3
• Adjust medication dose based on thyroid function tests

Common Pitfalls to Avoid

• Failing to recognize thyroid storm (life-threatening emergency) 1
• Missing the underlying cause of hyperthyroidism 1
• Overlooking pregnancy status before treatment selection 1
• Inadequate monitoring of medication side effects 1, 3
• Ignoring cardiovascular complications of hyperthyroidism 1
• Not considering drug interactions with anticoagulants, beta-blockers, digoxin, and theophylline 3

Treatment Algorithm

1. Confirm diagnosis with suppressed TSH, elevated Free T4/T3
2. Determine etiology through clinical presentation, antibodies, imaging
3. Initial therapy:
   • Start methimazole (10-30 mg daily) for most patients
   • Use PTU if in first trimester of pregnancy
   • Add beta-blocker for symptomatic relief
4. Monitor thyroid function every 2-3 weeks initially
5. Consider definitive therapy (RAI or surgery) if:
   • Large goiter
   • Medication intolerance
   • Patient preference
   • Recurrent disease after medication course

This approach prioritizes treatments with the best outcomes for morbidity, mortality, and quality of life while considering patient-specific factors.